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EDISON  AND  HIS  INVENTIONS 

WITH  COMPLETE 

ELECTRICAL  DICTIONARY. 


EDISON 

AND 

HIS  INVENTIONS 


INCLUDING  THE  MANY 


INCIDENTS,  ANECDOTES,  AND  INTERESTING  PARTICULARS 

CONNECTED  WITH  THE  EARLY  AND  LATER  LIFE 

OF  THE  GREAT  INVENTOR. 


FULL  EXPLANATIONS  OF  THE  NEWLY  PERFECTED  PHONO- 
GRAPH, TELEPHONE,  TASIMETER,  ELECTRIC  LIGHT, 
AND  ALL  HIS  PRINCIPAL  DISCOVERIES,  WITH 
COPIOUS  ILLUSTRATIONS. 


"T.  A.  E.  never  had  any  boy-hood  days;   his  early  amusements  were  steam 
engines  and  mechanical  forces." 

—SAMUEL  EDISON,  (concerning  his  son.) 


EDITED  BY 

J.  B.  McCLURE,  M.  A. 


COPYRIGHT,  RHODES  &  MOCLUBE  PUBLISHING  COMPANY,  1889.    ALL 
BIGHTS  RKSEBVED. 


CHICAGO. 
RHODES   &   MoOLUKE   PUBLISHING   COMPANY, 

1889. 


In  the  fractional  moment  of  the  world's  history,  like  its 
own  self,  Electrical  Science  has  suddenly  flashed  into  general 
utility,  and  is  now  rapidly  lifting,  not  only  the  veritable 
darkness  from  the  earth,  but  everywhere  in  home  and  office, 
field  and  mine,  on  land  and  sea,  is  demonstrating  a  scope  of 
usefulness  commensurate  with  the  loftiest  aspirations  of  man. 

Very  circumscribed  must  be  the  mind,  and  decidedly  lim- 
ited the  vision  of  him  who  can  take  no  interest  now  in 
both  the  actual  and  possible  verities  of  Electricity. 

Its  position  is  one  of  popular  supremacy,  from  which  its 
blessings  fall  upon  the  day,  no  less  than  the  night,  and  from 
which  the  weary  spaces  and  even  time  itself,  seem  to  flee 
away.  What  it  really  is,  no  one  knows;  but  what  it  is  ac- 
tually doing  this  book  clearly  tells  in  its  sketch  life  of 
Thomas  Alva  Edison,  the  self-made  electric  king  of  the 
nineteenth  century.  So  numerous  are  his  inventions  in 
every  department  of  this  wonderful  science,  and  so  fully  are 
they  described  in  this  volume — and  generally  by  Mr.  Edi- 
son himself — that  a  careful  perusal  leaves  little  or  nothing 
else  to  be  known  of  what  is  practical,  just  now,  in  this  mar- 
vellously interesting  field. 

Connected  with  the  life  o.  such  a  person,  there  is  always 
an  array  of  incident  and  anecdote  in  which  a  generous  pub- 
lic manifest  a  keen  interest  that  enlightens  and  entertains. 


URL 


It  has  been  our  aim,  also,  in  this  volume,  to  present  the  many 
stories  and  remarkable  experiences  of  his  early  and  later 
life  that  make  up  the  wonderful  history  of  Mr.  Edison. 

Nine  years  ago  the  first  edition  of  this  work  was  issued. 
The  world  was  intensely  expectant  then  as  to  what  Edison 
might  discover  along  the  line  of  the  mystic  science;  many 
doubted,  some  laughed,  and  a  few  scientists  who  should 
have  known  better,  scoffed  and  said,  "  No,  it  is  impossible." 
This  was  a  period  of  great  struggle  with  Mr.  Edison,  and 
yet  not  without  hope.  No  one  knows  this  better  than  the 
great  inventor  himself.  But  where  are  the  scoffers  now? 
And  what  the  stupendous  array  of  facts?  Into  his  Electric 
Light  alone  has  gone  $25,000,000,  with  more  to  follow!  to 
say  nothing  of  his  many  other  inventions,  one  of  which,  and 
the  latest,  his  perfected  Phonograph,  he  is  said  recently  to 
have  sold  for  a  "  cool  million  "  of  dollars.  Verily  the 
laborer  is  worthy  of  his  reward. 

There  can  be  no  doubt,  Electricity  "  has  come  to  stay." 
Its  mission  is  "  business."  And  we  shall  probably  yet  see 
the  "  lightning  all  round  the  horizon."  Mr.  Edison  still 
"has  the  floor."  Let  us  listen. 

We  retain,  unchanged,  the  full  details  of  Edison's  early 
struggles  with  the  Electric  Light  and  Phonograph  —  all  the 
more  interesting  now  —  and  add  the  full  particulars  of  his 
great  success  in  these  departments;  also  a  chapter  on 
"  Menlo  Park  "  and  its  noble  Edisonian  band  of  workers  in 
days  of  yore  has  not  been  altered. 

The  reader  will  find  quite  an  extended  Electrical  Diction- 
ary at  the  close  of  this  volume  that  fully  explains  the  many 
newly  coined  words  and  phrases  required  in  this  new  and  rap- 
idly enlarging  field,  which  are  not  found  in  Webster's  Un- 
abridged, and  which  constitute,  as  a  whole,  an  interesting 
and  instructive  epitome  of  practical  Electricity. 

We  acknowledge  our  obligations,  in  the  preparation  of  this 
work,  to  Samuel  Edison,  Esq.—  father  of  the  inventor  —  of 
Port  Huron,  Mich.;  Messrs.  Edison,  Batchelor,  Griffin,  and 
i 


other  associates  o^  Mr.  Edison;  Geo.  B.  Prescott's  works; 
Thomas  D.  Lockwood's  works;  Scribner;  North  American 
Review;  and  the  following  popular,  practical  and  progres- 
sive electric  periodicals:  THE  ELECTRICAL  WORLD,  New 
York  and  Chicago;  THE  ELECTRICAL  REViEW,No.l3  Park  Row, 
New  York;  THE  WESTERN  ELECTRICIAN,  Lakeside  Building, 
Chicago;  and  especially  to  Mr.  E.  L.  Powers,  the  Chicago 
Manager  of  the  ELECTRICAL  WORLD,  Lakeside  Building.  Our 
thanks  and  best  wishes  to  all  these  industrious  workers  on 
"  the  confines  of  the  knowable." 

The  highest  honors,  official  and  social,  have  been  conferred 
upon  Mr.  Edison,  by  the  great  Paris  Exposition  of  1889, 
where  his  many  exhibits  form  the  greatest  wonder  of  all, 
unless  it  be  his  personal  self,  whose  attentions  from  the 
many  thousands  present  exceed  those  of  kings.  Such  is  the 
merited  and  wide-spread  compliment  bestowed  upon  the  hero 
of  this  volume. 

Chicago,  Jan.  2nd,  1890.  J.  B.  McCLURE. 


A  CHAPTER  OF  SOME  CURIOUS  FEATURES  IN  ELECTRICITY,  264 

A  DESCRIPTION  OF  THE  PHONOGRAPHIC  RECORDS  UNDER 
THE  MICROSCOPE — How  the  letters  look — Believed 
by  Edison  to  be  legible — The  deepest  indentations 
made  by  consonants, 85 

A  GREAT  AND  WONDERFUL  INSTRUMENT  NOW  COM- 
PLETED— The  new  Phonograph  as  explained  fully  by 
Mr.  Edison — What  it  is,  what  it  does,  and  what  it 
may  yet  do, 216 

A  LITTLE  CHAT  INTERMINGLED  WITH  WHISPERS  WITH 
PERSONS  210  MILES  APART — An  innocent  joke  per- 
petrated on  Mr.  Firman — Complete  success  of  the 
Carbon  Telephone, 112 

A    MONUMENT    TO    ELECTRICITY — Mr.    Edison's    New 

Laboratory  at  Orange,   N.  J.          -         -         -         -     24 

A  STORY  OF  EDISON — Hurrying  up  the  Phonograph,     -  231 

A  SERIES  OF  REMINISCENCES  OF  EDISON  AS  "  TRAIN 
BOY  " — His  success  in  selling  apples,  toys,  periodi- 
cals, etc.,  on  the  train — How  he  used  the  Telegraph 
— He  starts  a  Newspaper — The  Edison  Duplex — 
His  Laboratory  on  wheels — A  great  mishap — Young 
Edison  pitched  off  the  train,  -  -  -  -  -37 

A  VERY  YOUNG  ELECTRICIAN — He  buys  a  book  on  Elec- 
tricity— Extemporizes  a  short  line — The  Tom  Cat 
Electrical  Battery — A  daring  feat  in  front  of  a  loco- 
motive— The  young  Son  of  Thunder  getting  down 
to  business — Interesting  Anecdotes,  -  -  -  47 


A  YOUNG  OPERATOR — His  engagement  at  Port  Huron — 
Resigns — Goes  to  Stratford — Rigs  an  Ingenious 
Machine — Telegraphing  by  Steam,  -  -  -  53 

A  YOUNG  INVENTOB  AND  OPERATOR — Invents  an  instru- 
ment— Tells  the  boys  to  "  rush  him  " — Fidelity  re- 
warded— Becomes  a  first-class  operator,  -  -  56 

.^EROPHONE — An  Instrument  for  enlarging  the  volume 

of  sound — Illustrated,       -        -        -         -        -        -140 

AN  ACCOUNT    OF   EARLY  REMINISCENCES,  AS  GIVEN, BY 

EDISON'S  FATHER, 46 

BOSTON  AND  YOUNG  EDISON — He  departs  for  the  "Hub" 
— Snow  bound— His  reception — Joke  on  the  cock 
roaches — Inventions — The  girls,  -  -  -  -  62 

BURDETTE  AND  EDISON  TESTING  THE  SPANKTROPHONE,  116 

CARBON  RHEOSTAT, 138 

DAWDLES  TRIES  THE  TELEPHONE,      -          -          -         -  119 

DICTIONARY  OP  ELECTRICAL  WORDS  AND  PHRASES, 
FULLY  EXPLAINED  (NOT  FOUND  IN  WEBSTER) — 
Giving  an  easy  outline  of  the  science  of  electricity,  237 

DOLL  BABY  PHONOGRAPH, 231 

DOWN  IN  THE  GOLD  MINES  OUT  WEST,      -        -         -124 

DYNAMO  FULLY  EXPLAINED — A  wonderful  mechanism 

for  generating  electricity, 173 

DYNAMO  INSTRUCTIONS  IN  FULL  DETAIL — Showing  how 

to  run  it  properly, 179 

EARLY  EFFORTS  ON  THE  PHONOGRAPH — The  Edison  & 
Faber  talking  machines — Phonographic  possibilities 
now  realized, 75 

EDISON   BUILDING,  CHICAGO, 196 

EDISON  IN  NEWARK,      --         ....-66 

8 


EDISON   IN  NEW    YORK — Penniless  and  hungry — The 

supreme  moment — Brains — His  great  success,          -    64 

EDISON  IN  MENLO    PARK   AND    His   EARLY   BAND   OP 

INDUSTRIOUS  WORKERS, 69 

EDISON'S  EARLY  LIFE — His  nativity — Childish  amuse- 
ments— His  ancestry — Mrs.  Nancy  Elliott  Edison 
— Edison's  happy  home — Early  education,  -  -  26 

EDISON'S  UPS  AND  DOWNS — The  Inventor  vs.  the  Oper- 
ator— Thunder  all  'round  the  horizon — Footing  it 
in  Tennessee — Off  for  South  America — "Run"  on  a 
bank — Incidents, 58 

EDISON'S  COURTSHIP  AND  MARRIAGE,     -        -        -        -     67 

EDISON'S  FUNNY  ANECDOTE  OF  THE  ROCKY  MOUNTAIN 

SCOUTS,  -  125 

EDISON'S  BRIDGE  FOR  MEASURING  MAGNETIC  CONDUC- 
TIVITY, ........  212 

EDISON'S  DYNAMO  FOB  GENERATING  ELECTRICITY,          -  173 

EDISON'S  ELECTRIC  LIGHT  AS  EXPLAINED  BY  HIMSELF  IN 
FULL  DETAIL  WITH  ILLUSTRATIONS  ;  How  IT  is 
MADE,  ETC., 159 

EDISON'S  ELECTRIC  LIGHT  vs.  JABLOCHOFF'S  et  al.— 
Sub-division  of  the  fluid — Platinum  and  Iridium — 
How  the  light  appeared  to  a  visitor — Carbon  candle 
— Early  efforts, 148 

EDISON'S  ELECTRIC  LIGHT  IN  THE  ROOKERY  BUILDING  IN 

CHICAGO — One  of  the  largest  plants  in  the  world,    -  190 

EBISON'S  ELECTRIC  PEN, 95 

EDISON'S  GROUND  DETECTOR  FOR  LIGHT  CIRCUITS,          -  198 

EDISON'S  HARMONIC  ENGINE, 144 

EDISON'S  HIGH  ECONOMY  CONVERTOR,      -        -        -       -  193 
0 


EDISON'S  IMPROVED  PHONOPLEX  FOR  TELEGRAPHING  SEV- 
ERAL MESSAGES  ON  THE  SAME  WIRE  AT  THE  SAME 
TIME, 209 

EDISON'S  EARLY  EFFORTS  IN  ELECTRIC  LIGHT  EXPERI- 
MENTS,   154 

EDISON'S  JUNCTION  Box  AND  SAFETY  CATCH,  -  -  208 
EDISON'S  METERS  FOR  MEASURING  ELECTRICITY,  -  -  202 
EDISON'S  METHOD  OF  REGULATING  THE  CURRENT,  -  -  201 

EDISON'S  MIMEOGRAPH, 208 

EDISON'S  MUNICIPAL  INCANDESCENT  LAMP  FOR  OUTSIDE 

LIGHTING, 186 

EDISON'S  NEW  CUT-OUT — An  ingenious  mechanism  to 
prevent  a  long  line  of  lamps  from  being  suddenly 
extinguished,  - 189 

EDISON'S  OPINION  OF  THE  PATENT  LAW — A  plain,  pung- 
ent statement  for  Congressmen,  ....  233 

EDISON'S  PYRO-MAGNETIC  DYNAMO — A  mechanism  gen- 
erating electric  energy  from  the  heat  of  a  storm,  - 182 

EDISON'S  PERFECTED  PHONOGRAPH,        -        -        -        -  216 

EDISON'S  PHONOMETER, 142 

EDISON'S  PRINCIPAL  INVENTIONS,  -  -  •  •  -  71 
EDISON'S  PET  BABY,  -  -  -  -  •  -  -121 

EDISON'S  QUADRUPLEX, 73 

EDISON'S  RHEOSTAT — For  regulating  the  resistance  of 

electricity, 138 

EDISON'S  SONOROUS  VOLTAMETER, 123 

EDISON'S  TELEPHONE — Full  explanations — Illustrated,  -  98 
EDISON  JOKING  WITH  THE  EARLY  PHONOGRAPH,  -  -  94 
EDISON  JOKING  WITH  HIS  FRIENDS,  -  -  -  -  123 
EDISON  ON  STORAGE  BATTERIES,  -----  185 
10 


ELECTRIC  MOTOR, 181 

ELECTRO-MOTOGRAPH — A   curious    instrument — How  it 

works — Four  hundred  moves  in  a  second,         -         -     96 

ELI  PERKINS  AND  MR.  EDISON, 117 

ETHERIC  FORCE — A  curious  discovery  of  Mr.  Edison,     -  147 

FUNNY  SIDE  OF  THE  PHONOGRAPH,   AS   SEEN  BY   COL. 

KNOX, -  229 

FURTHER  EXPERIMENTS  PERTAINING  TO  LIGHTS,  LAMPS, 

AED  THE  GENERATING  OF  ELECTRICITY,  -         -  159 

How  THE  PHONOGRAPH  MAN  AMUSES  HIMSELF,  -        -     91 
How  THE  PHONOGRAPH  FRIGHTENED  A  PREACHER,       -     92 

How    THE    PHONOGRAPH    WAS    DISCOVERED    BY    MR. 

EDISON, 93 

How  TO  PUT  THE  DYNAMO  IN  OPERATION,    -        -        -  176 

LITTLE    SUNS    MADE    FROM    BURNT    PAPER — A  great 

wonder,          __..-_.-  159 

MEGAPHONE,         -        -        ...        -        -        -        -  122 
MOSES  AND  THE  TODDYGRAPH,  -     90 

MOTOGRAPH  RECEIVER — A  curious  instrument,      -        -  146 
NEW  EDISON  DYNAMO,          -        -        -        -        -        -173 

OUR  AGE  AND  ITS  HERO, 17 

PERSONAL  DESCRIPTION  OF  MR.  EDISON,  ETC.,      -         -     20 

PHONOGRAPH  AS  NEWLY  PERFECTED  FULLY  EXPLAINED, 

BY  MR.  EDISON,      -  -  216 

PHONOGRAPH  AND  Music — What  it  can  do,    ...  228 
PHONOGRAPH  SUPREME  AT  HOME,  -----    88 

PHONOGRAPH'S  ARRIVAL  «  OUT  WEST" — It  visits  Chi- 
cago— Is  interviewed  by  a  reporter — A  modern 
miracle — How  it  talked — What  it  had  to  say,  -  82 

11 


\ 


POSSIBILITIES  OF  THE  PHONOGRAPH — A  short  hand  re- 
porter— Elocutionist  —  Opera  singer — Teacher  of 
languages — Its  medical  possibilities,  -  -  -  80 

PEESSUKE  RELAY — A  very  useful  instrument,         -  -  136 

RELATIVE  CONDUCTIVITY  OF  SUBSTANCES,     -        -  -  263 

SEA  TELEPHONE — How  ships  may  talk  on  the  sea,  -  -  209 

TABLES  OF  WEIGHT  AND  LINEAL  MEASURE,  ETC.  -  263 

TASIMETER  OR  THERMOPILE — An  instrument  that  meas- 
ures the  heat  of  the  stars — How  it  is  done — Full 
account  of  its  discovery,  -  -  -  -  -126 

TASIMETER  AND  THE  STARS, 128 

TESTING  THE  TASIMETER  ON  THE  SUN'S  CORONA — "Won- 
derful experiments  of  Mr.  Edison  in  the  Rocky 
Mountains,  -  -  -  -  -  -  -  -129 

TELEPHONE — Mr.  Edison's  own  account  of  his  discovery 
of  the  Carbon  Telephone — An  interesting  history— 
His  explanation  of  the  wonderful  instrument — Illus- 
trated by  numerous  engravings — It  talks  over  a  wire 
720  miles  long — His  other  telephones,  -  -  98 

TELEPHONE  AND  THE  DOCTORS,      -        -        -        -        .119 

TELEPHONOGRAPH — A  combination  of  the  telephone  and 

phonograph,  -         -         -         -         -         -         -121 

THE  BASIS  OF  THE  TASIMETER, 132 

TRAIN  TELEGRAPHY — How  a  telegram  may  be  sent  or 

received  on  a  rapidly  moving  train,         -         -         -  204 

UNCLE  REMUS  AND  THE  PHONOGRAPH,  -        -        .89 

WONDERFUL  OLFACTORY  POWERS  OF  THE  TELEPHONE,  -  115 


Aerophone,  (1)   (2) 140 

Amperemeters  and  Regulator  Boxes 192 

An  Early  Generator 171 

Apparatus  of  the  Telephone 104 

Bergmanns  &  Go's  Manufactory  of  Edison's  Electric  Ap- 
pliances  227 

Bridge  for  Measuring  Magnetic  Conductivity 213 

Carbon  Rheostat  (perspective,) _139 

Carbon  Rheostat  (in  section,) 139 

Carbon    Spiral __ _ 161 

Cat  Battery  Experiment 49 

Continental  Bill__ 29 

Diagram  of  the  Phonograph 78 

Different  Types  of  the  Edison  Dynamo 178 

Dynamo  in  Operation 175 

Dynamo,  New  Edison 173 

Dynamo  Room  in  the   Rookery  Building,  Chicago 191 

Edison   Building,  Chicago 197 

Edison  "Ground"  Detector 199 

Edison  Lamp  Company's  Factory,  Newark,  N.  J 195 

Edison  Municipal  Incandescent  Lamp 187 

Edison  Rescuing  a  Child 50 

13 


Early  Incandescent  Lamp 165 

Edison  Telegraphing  by  Steam 55 

Edison's  Electric   Generator 155 

Edison's  Electric  Light 157 

Edison's  Pyro-Magnetic  Dynamo 183 

Electric  Lamp 169 

Electric  Light " 153 

Electric  Pen __ 95 

Electro-Mechanical  Telephone 169 

Electrophorous  Telephone 108 

Electro-Static  Telephone __ ___109 

Harmonic  Engine 144 

House  in  which  Edison  was  Born 27 

Incandescent  House  Lamp 194 

Lever  Signal 106 

Local  Lamp 161 

Menlo  Park,  the  Birth-place  of  the  Incandescent  Lamp..  16 

Micro-Tasimeter  (perspective) _133 

Micro-Tasimeter  (in  section) ___133 

Micro-Tasimeter  (entire) 133 

Motograph  Receiver 146 

Mrs.  Nancy  E.  Edison,  Mother  of  the  Inventor __  31 

Offices  and  Show  Rooms  of  the  Edison  United  States  Manu- 
facturing Co.,  New  York 236 

Operator  Receiving  and  Sending  Messages  on  a  Railway 
Train _ ___204 

Operator's  Train  Telegraph  Apparatus 207 

14 


Pendulum  Signal ___ 107 

Phonograph  Perfected — The  Wonder  of  the  World — Fully 

Explained  by  Mr.  Edison __217 

Phonograph  in  Operation 75 

Phonograph  Records  under  the  Microscope 87 

Phonometer 142 

Pressure  Relay 137 

Printing  the  "  Grand  Trunk  Herald  "  on  the  Train 39 

Quadruplex 74 

Railway  Car  Showing  How  to  Telegraph   on  a  Moving 

Train 205 

Samuel  Edison,  Father  of  the  Inventor 31 

Tasimeter __ __ _..128 

Telephone  Apparatus,  with  Switch 105 

The  Telephone  (interior) __.  98 

The  Telephone  (exterior) __ 98 

The  Telephonograph___ 121 

Thomas  Alva  Edison Frontispiece 

Tuning  Fork  Signal ___ ___107 

The   Sea 210 

Water  Telephone 110 

Young  Edison's  Mishap — Car  on  Fire 36 

Young  Edison  Pitched  Into  the  River 43 

Zircon  Burner..  __160 


15] 


EDISON  AND  HIS  INVENTIONS. 


Our  Age  and  Its  Hero. 

"  Of  what  use  is  it?  "  said  the  skeptic  to  Franklin,  doubt- 
ing the  value  of  his  identification  of  lightning  and  electricity. 
"  Of  what  use  is  a  child?  "  said   the   philosopher,  adding 
"  It  may  become  a  man." 

Evidently,  this  "  man  with  the  kite  "  saw  the  coming  pos- 
sibilities of  the  "  subtle  fluid,"  but  it  is  hardly  possible  that 
he  dreamed  of  its  ultimate  widespread  general  utility.  "  We 
put  it  now,"  says  Professor  Gray,  "  to  all  sorts  of  uses.  We 
make  it  carry  our  messages,  drive  our  engine,  ring  our  door 
bell,  and  scare  the  burglar.  We  take  it  as  a  medicine,  light 
our  gas,  see  by  it,  hear  from  it,  talk  with  it,  and  now  we  are 
beginning  to  teach  it  to  write.  If  Job  lived  in  this  age, 
and  the  question  was  put  to  him  as  of  old,  «  Canst  thou 
send  lightnings,  that  they  may  go  and  say  unto  thee,  <  Here 
we  are?"  he  could  say,  'Yes;'  and  they  can  be  made  to 
say  it  in  the  vernacular."  "  A  friend  of  mine  says  in  verse," 
adds  the  professor: 

"  Time  was  when  one  must  hold  bis  ear 

Close  to  a  whispering  voice  to  hear- 
Like  deaf  men,  nigh  and  nigher; 

But  now  from  town  to  town  he  talks, 

And  puts  his  nose  into  a  box 

And  whispers  through  a  wire. 
"  In  olden  times  along  the  street 

A  glimmering  lantern  led  our  feet 

When  on  a  midnight  stroll; 

But  now  we  snatch,  when  night  comes  nigh, 

A  piece  of  lightning  from  the  sky 

And  stick  it  on  a  pole." 


i8  THOMAS  A.  EDISON 

Yes,  the  "  child  has  become  a  man,"  noble,  honest,  useful, 
good  and  great.  It  has  had  a  singularly  long  period  of  in- 
fancy, but  a  decidedly  brief  boyhood.  As  Samuel  Edison 
says  of  his  son,  the  great  inventor,  so  has  it  been  with 
electricity:  "T.  A.  E.  never  had  any  boyhood  days;  his 
early  amusements  were  steam  engines  and  mechanical  forces." 
"  Those  of  us  who  are  just  across  the  meridian  of  life," 
says  Gray,  "  can  remember  the  first  telegraph  wire  that  was 
strung  in  this  country.  To-day  it  is  difficult  to  find  a  cor- 
ner of  the  earth  so  remote  as  to  be  out  of  sight  of  one. 
You  will  find  them  even  in  the  bottom  of  the  seas  and 
oceans.  The  last  twenty  years  have  seen  more  advance  in 
the  science  of  electricity  than  all  the  6,000  historic  years 
preceding.  More  is  discovered  in  one  day  now  than  in  a 
thousand  years  of  the  middle  ages,  so  that,  literally,  '  a  day 
is  a  thousand  years.' " 

Inventions  multiply  with  increasing  rapidity,  and  dis- 
coveries flash  as  lightnings  over  the  land.  We  cannot,  if  we 
would,  shut  our  eyes  to  the  results. 

Intimately  associated  with  this  progress,  and  foremost  in 
the  ranks,  is  Thomas  Alva  Edison,  the  acknowledged  leader 
in  "  applied  electricity,"  a  veritable  "  captain  of  industries," 
whose  multiplied  and  multiplying  useful  electrical  mechan- 
isms have  become  to  men  of  thought,  the  wonder  of  the 
world. 

Since  the  first  Edison  dynamo  was  built,  for  the  unfortu- 
nate steamer  "  Jeannette,"  which  now  lies  with  it  in  the 
cold  depths  of  the  Arctic  Ocean,  over  one  hundred  and  fifty 
central  stations,  and  nearly  two  thousand  isolated  plants, 
with  a  capacity  of  more  than  one  million,  five  hundred 
thousand  lamps,  have  been  installed  in  America  alone,  to  sup- 
ply the  Edison  incandescent  electric  light,  aggregating  an 
expenditure  of  many  millions  of  dollars.  Other  plants  are 
to  follow,  one  of  which,  the  great  Auditorium  Building  in 


AND  HIS  INVENTIONS.  19 

Chicago,  will  be  the  largest  isolated  plant  in  the  world,  con- 
taining eight  thousand,  six  hundred  lights,  now  in  process  of 
installation.  And  all  this,  in  the  line  of  only  one  great  pur- 
pose of  the  Edison  discoveries,  the  electric  light,  involving, 
however,  about  one  thousand  separate  patents! 

Verily,  these  facts  demonstrate  not  only  the  genius,  but 
the  persistent  energy  and  dominant  determination  of  Mr. 
Edison,  to  subordinate  the  occult  forces  of  the  mystic 
science  to  his  end  and  aims,,  and  also  verify  his  remarkable 
words,  uttered  some  four  ve^rs  ago  only,  concerning  the 
"  commercial  evolution  of  electricity,"  amid  the  laughs  and 
jeers  of  many,  and  exciting  great  criticism  at  the  time,  when 
he  said:  "  Two  years  of  experience  proves  beyond  a  doubt 
that  the  electric  light  for  household  purposes  can  be  pro- 
duced and  sold." 

Professor  Barker  may  well  say,  as  he  has,  of  Mr.  Ed- 
ison, that  "  He  is  a  man  of  Herculean  suggestiveness;  not 
only  the  greatest  inventor  of  the  age,  but  a  discoverer  as 
well;  for,  when  he  cannot  find  material  with  properties  he  re- 
quires, he  reaches  far  out  into  the  regions  of  the  unknown, 
and  brings  back  captive  the  requisites  for  his  inventions." 

Recently,  at  a  concert  in  the  Crystal  Palace,  London,  Edi- 
son's new  phonograph  recorded  perfectly  a  performance  of 
Handel's  music,  reporting  with  perfect  accuracy  the  sublime 
strains  of  the  "  Israel  in  Egypt,"  and  which  can  now  be 
repeated  at  any  time  and  place  with  the  phonogram  and  a 
"  reproducer." 

By  Edison's  automatic  system  one  thousand  words  per 
minute  are  possible  over  a  single  wire;  by  his  quadruplex, 
four  distinct  and  different  messages  pass  over  the  wire  at  the 
same  time;  by  his  phonograph  all  shades  of  sound  are  pre- 
served and  may  at  any  time  be  reproduced;  by  his  carbon 
telephone  all  shades  of  sound  pass  over  the  long  wires  to  be 
distinctly  heard  many  miles  away;  and  by  his  electric  light, 


20  THOMAS  A.  EDISON" 

night,  with  its  darkness,  is  disappearing  from  the  arena  of 
civilization.  Thus  the  wide  world,  every  day,  by  this  great 
man,  is  being  brought  into  closer  proximity,  with  its  facili- 
ties for  communication,  business,  social  life  and  pleasures,  al- 
most infinitely  augmented. 

Well  may  a  leading  journal  of  this  country  remark:  <{  There 
can  be  no  doubt  that  Mr.  Edison,  the  inventor  of  the  phono- 
graph, is  one  of  the  most  remarkable  men  cf  the  present 
century.  His  improvements  in  telegraphic  apparatus,  and  in 
the  working  of  the  telephone,  seem  almost  to  have  exhausted 
the  possibilities  of  electricity.  In  like  manner  the  discov- 
ery of  the  phonograph  and  the  application  of  its  principles 
in  the  aerophone,  by  which  the  volume  of  sound  is  so  ampli- 
fied and  intensified  as  to  be  made  audible  at  a  distance  of 
several  miles,  seem  to  have  stretched  the  laws  of  sound  to 
their  utmost  limit.  We  are  inclined  to  regard  him  as  one  of 
the  wonders  of  the  world.  While  Huxley,  Tyndall,  Spencer 
and  other  theorists  talk  and  speculate,  he  quietly  produces 
accomplished  facts,  and,  with  his  marvelous  inventions,  is 
pushing  the  whole  world  ahead  in  its  march  to  the  highest 
civilization,  making  life  more  and  more  enjoyable." 


Personal  Description. 

OF  MEDIUM  SIZE — FINE  LOOKING,  COMPANIONABLE,  UNOS- 
TENTATIOUS— GREAT  ENERGY,  PERSEVERANCE — AN  IN- 
TERESTING ANECDOTE. 

Mr.  Edison  is  a  very  pleasant  looking  man,  of  the  av- 
erage size,  five  feet  ten  inches  high,  fair  complexion,  with 
dark  hair  considerably  silvered,  and  wonderfully  piercing 
gray  eyes.  The  latter  are  almost  veritable  electric  lights, 
and  when  engaged  in  deep  thought  their  look  is  intense,  in- 
dicative of  decided  penetration  and  acute  analysis.  His 


AND  HIS  INVENTIONS.  21 

features  are  well  outlined  in  the  engraving  we  present,  and 
show  him  to  be  a  man  remarkably  adapted  to  his  line  of 
labor. 

He  is  now  forty  years  of  age.  His  residence  is  at  Llew- 
ellyn Park,  Orange,  N.  J.,  where  he  has  a  fine  home,  with  all 
the  pleasant  surroundings  that  a  magnificent  country  seat 
requires.  He  lost  his  first  wife  several  years  since,  the  in- 
dulgent mother  of  two  dear  children,  "  Dot  "  and  "  Dash." 
Some  two  years  ago  he  married  Miss  Minnie  Miller,  the 
daughter  of  the  well  known  manufacturer  and  capitalist  of 
that  name  residing  at  Akron,  Ohio.  A  third  child  has  come 
upon  the  stage,  who  is  the  "  little  one "  of  this  pleasant 
family  of  five,  and  is  the  "  baby  "  elsewhere  mentioned  in 
this  volume,  the  record  of  whose  varied  vociferations  Mr. 
Edison  is  said  statedly  to  be  recording  with  his  wonderful 
phonograph,  just  to  show  it  after  a  while  when  it  has  grown 
to  young  womanhood  how  it  could  and  did,  without  a  doubt, 
chirrup,  cry  and  laugh  during  the  infantile  period. 

It  is  here,  also,  at  Orange,  that  Mr.  Edison  has  located  his 
newest,  best  and  very  extensive  laboratory,  which  is  fully 
equipped  with  every  possible  convenience  for  turning  out  his 
many  and  remarkable  inventions.  It  is  in  this  immense  es- 
tablishment, completed  at  great  expense,  and  manned  by  a 
noble  body  of  faithful,  intelligent  and  competent  assistants, 
many  of  whom  were  at  Newark  and  Menlo  Park,  that  Mr. 
Edison  is  quite  at  home  and  fully  master  of  the  situation. 

When  in  this  vast  workshop,  the  great  inventor  is  too 
studious  to  care  much  for  his  dress  and  general  make-up.  On 
such  occasions  he  appears,  like  other  hard-working  men,  of- 
ten the  "  worse  for  wear,"  with  acid-stained  garments,  dusty 
eye-brows,  discolored  hands  and  dishevelled  hair.  Under 
such  circumstances  he  has  been  correctly  noted  by  reporters 
as  "  considering  time  too  valuable  to  waste  on  personal  deco- 
ration," his  boots  often  "  not  blackened,"  and  his  hair  ap- 


22  THOMAS  A.  EDISOK 

pearmg  as  if  "  cut  by  himself."  But  at  the  proper  time 
and  place,  when  a  better  appearance  is  requisite,  he  is  always 
equal  to  the  occasion,  being  "  clean  shaven,"  handsomely 
attired  in  the  most  approved  style,  wearing  a  number  seven 
and  seven-eights  silk  hat,  and  is  every  whit  a  noble-looking 
man. 

Mr.  Edison  is  social  by  nature,  and  very  companionable  to 
those  who  enjoy  his  confidence.  He  loves  to  converse  with 
those  interested  in  his  inventions,  and  particularly  so  if  his 
discoveries  are  comprehended.  His  geniality  has  made  for 
him  a  host  of  friends,  and  gathered  about  him  a  band  of 
workers,  some  of  whom  have  been  with  him  for  many  years. 
In  his  family  he  is  affectionate  and  generous,  a  kind  husband 
and  indulgent  father,  caring  little  for  the  ordinary  manner- 
isms of  life,  and  always  reaching  the  point  by  the  nearest 
road.  Withal  he  has  a  well  defined  vein  of  humor  that  is 
always  seen  at  the  right  time,  and  that  not  infrequently 
assumes  the  aspect  of  a  joke.  Thus  he  occasionally  threat- 
ens to  adjust  an  invention  of  some  kind  to  his  gate  at  the 
factory  that  will  deter  visitors  from  entering,  perchance 
knock  them  down,  but  the  gate  yet  swings  harmlessly  and 
hosts  of  visitors  pass  in  and  out. 

His  personal  tastes  are  very  simple,  and  he  is  thoroughly 
unostentatious.  When  invited  some  time  since  to  a  dinner 
at  Delmonico's,  he  satisfied  himself  with  a  piece  of  pie  and 
cup  of  tea,  greatly  to  the  astonishment  of  his  host,  who 
wished  to  do  "  the  handsome  thing."  On  one  occasion  when 
tendered  a  public  dinner,  he  declined,  stating  that "  one 
hundred  thousand  dollars  would  not  tempt  him  to  sit  through 
two  hours  of  personal  glorification."  Personal  notoriety  he 
dislikes,  and  aptly  says  "  a  man  is  to  be  measured  by  what  he 
does,  and  not  by  what  is  said  of  him." 

His  habits  are  peculiar,  consequent  upon  his  intense  devo- 
tion to  discovery.  When  in  the  throes  of  invention,  he 
scarcely  sleeps  at  all,  and  is  equally  as  irregular  concerning  his 


AND  HIS  INVENTIONS.  23 

eating.  "  Speaking  of  his  early  work  in  Newark,"  says  Mr. 
Johnson,  a  co-laborer,  "  he  averaged  eighteen  hours  a  day." 
Says  the  same  gentleman:  "  I  have  worked  with  him  for  three 
consecutive  months,  all  day  and  all  night,  except  catching 
a  little  sleep  between  six  and  nine  o'clock  in  the  morning." 
At  Newark,  on  the  occasion  of  the  apparent  failure  of  the 
printing  machine  he  had  taken  a  contract  to  furnish,  he 
went  up  into  the  loft  of  his  factory  with  five  assistants, 
and  declared  he  would  not  come  down  till  it  worked.  It 
took  sixty  hours  of  continuous  labor,  but  it  worked,  and 
then  he  slept  for  thirty.  His  perseverance,  patience,  endur- 
ance, determination  and  industry  are  very  remarkable,  and 
perhaps  without  parallel.  The  routine  of  his  day,  it  is  well 
said,  "  is  a  routine  of  grand  processes  and  ennobling  ideas." 
The  following  story  fairly  illustrates  the  scope  of  Mr. 
Edison's  labor  in  reaching  a  single  point:  In  the  develop- 
ment of  the  automatic  telegraph  it  became  necessary  to  have 
a  solution  that  would  give  a  chemically  prepared  paper  upon 
which  the  characters  could  be  recorded  at  a  speed  greater 
than  two  hundred  words  a  minute.  There  were  numerous 
solutions  in  French  books,  but  none  of  them  enabled  him  to 
exceed  that  rate.  But  he  had  invented  a  machine  that  would 
exceed  it,  and  must  have  the  paper  to  match  the  machine. 
"  I  came  in  one  night,"  says  Mr.  Johnson,  "  and  there  sat 
Edison  with  a  pile  of  chemistries  and  chemical  books  that 
were  five  feet  high  when  they  stood  on  the  floor  and  laid 
one  upon  the  other.  He  had  ordered  them  from  New  York, 
London  and  Paris.  He  studied  them  night  and  day.  He 
ate  at  his  desk  and  slept  in  his  chair.  In  six  weeks  he  had 
gone  through  the  books,  written  a  volume  of  abstracts,  made 
two  thousand  experiments  on  the  formulas  and  had  produced 
a  solution — the  only  one  in  the  world — that  would  do  the  very 
thing  he  wanted  done, — record  over  two  hundred  words  a  min- 
ute on  a  wire  two  hundred  and  fifty  miles  long.  He  has  since 
succeeded  in  recording  thirty-one  hundred  words  a  minute." 


24  THOMAS  A.  EDISON 

Edison's  Monument  to  Electricity. 

THE  NEW  LABORATORY  AT  LLEWELLYN  PARK,  ORANGE,  N.  J. 

The  finest  and  most  complete  laboratory,  doubtless,  to  be 
found  in  the  world,  Mr.  Edison  has  just  erected  at  Llewellyn 
Park,  Orange,  N.  J.,  where  he  and  his  faithful  and  competent 
assistants  now  spend  their  time  in  "  turning  out  inventions, 
with  two  one  hundred  and  fifty  horse-power  engines  back  of 
them."  "The  Electrical  Review,"  in  describing  this  estab- 
lishment, says : 

"  He  has  not  merely  a  laboratory  of  unequalled  extent,  but 
he  has  a  storehouse  of  everything,  a  perfectly  equipped 
machine  shop,  capable  of  turning  out  the  heaviest  as  well  as 
the  most  delicate  kinds  of  work,  with  workmen  of  the  highest 
skill  in  every  department;  a  veritable  central  station,  adapted 
to  furnish  any  desired  current  for  experiments;  a  chemical 
laboratory  of  the  most  complete  description;  a  scientific 
library  of  enormous  proportions;  and  in  short,  he  has  a  mod- 
ernized Aladdin's  Lamp,  by  whose  aid  every  wish  almost  can 
be  at  his  bid  ding  converted  into  an  accomplished  fact." 

In  the  chemical  department  of  this  institution  there  is  to 
be  found  samples  of  every  element  and  compound,  known 
and  unknown,  in  the  world,  in  quantities  to  meet  the  wants 
of  the  inventor  for  experimental  purposes;  even  the  teeth, 
fur,  skins,  etc.,  of  animals,  and  leaves,  grasses,  wood,  etc., 
from  every  clime. 

The  library  is  also  a  magnificent  affair.  It  is  a  spacious, 
high-ceiled  room,  with  three  tiers  of  alcoves  and  two 
balconies  around  the  room,  all  finished  elaborately  in  hard 
wood,  and  will  hold  about  100,000  volumes.  Though  not 
quite  filled,  it  will  soon  be,  at  the  rate  of  stocking  now  going 
on.  Tables  and  writing  desks  are  conveniently  arranged, 
and  any  given  subject  can  be  quickly  studied  up  in  comfort- 
able chairs,  under  a  strong  light  and  the  pleasant  surroundings 


AND  HIS  INVENTIONS.  25 

of  Turkish  rugs  and  exotic  plants.  Electric  lamps  are  every- 
where, ready  to  be  lighted  at  will,  both  here  in  the  library 
and  in  every  part  of  the  buildings. 

The  lecture  room  is  devoted  to  lectures  by  various  members 
of  Mr.  Edison's  staff,  and  these  are  given  on  regular  occasions. 
A  raised  platform,  with  experimental  tables  and  blackboards 
for  illustrations,  occupies  the  center  of  one  of  the  sides,  and 
at  the  walls  are  the  terminals  from  the  distant  dynamos  and 
batteries  ready  to  supply  current  for  all  sorts  of  experiments 
or  demonstrations. 

Altogether,  the  laboratory  has  not  its  equal  in  the  world. 
Mr.  Edison  has  personally  selected  his  assistants  and  work- 
men, the  requirement  being  the  highest  intelligence  and  skill; 
and  it  may  be  safely  said  that  nowhere  else  can  be  found  a 
corps  of  officers  and  workmen  combining  the  intellectual 
knowledge  and  mechanical  expertness  here  drawn  together. 

The  laboratory,  the  fulfilment  of  the  unexpressed  hopes  of 
the  genial  inventor  for  years  past,  would  seem  to  be  one  of 
his  greatest  achievements;  but  he  himself  considers  as  his 
greatest  work  the  establishment  and  successful  operation  of 
the  great  central  station  in  Pearl  street,  New  York  City.  The 
task  was  undertaken  at  a  time  when  absolutely  nothing  had 
been  done  from  which  example  could  be  taken.  There  were 
no  finger  posts,  no  beaten  paths,  nothing  but  a  wilderness  of 
darkness  and  obscurity.  Everything  had  to  be  invented,  the 
dynamos,  regulators,  indicators,  distributing  mains  and  feed- 
ers, house-wiring  devices,  meters,  lamps,  holders  and  a  myriad 
of  minor  details.  Yet  these  were  all  devised,  put  in  practical 
form,  applied,  the  greatnetwork  switched  in,  brushes  applied, 
steam  raised,  the  engines  started  and  thousands  of  lamps 
started  into  illuminated  life,  and,  not  the  least  extraordinary 
part  of  it,  from  that  moment  to  the  present,  there  has  not 
been  a  single  cessation  of  current  in  the  mains.  Truly  it  was 
a  great  work,  and  one  which  has  become  a  conspicuous  mile 
post  on  the  wayside  of  electrical  history. 


96  THOMAS  A.  EDISON 

Edison's  Early  Life. 

His  NATIVITY— CHILDISH  AMUSEMENTS— His  ANCESTRY— MRS.  NANCY 
ELLIOTT  EDISON— REMOVAL  TO  PORT  HURON- 
EDISON'S  HAPPY  HOME— EARLY 
EDUCATION. 

The  first  seven  years  of  young  Edison's  early  life  were  spent 
in  Milan,  Erie  County,  Ohio,  where  he  was  born  February  nth, 
1847.  At  this  time  Milan  was  a  young,  ambitious  and  prosper- 
ous town  of  three  thousand  inhabitants,  located  on  the  Huron 
River,  at  the  head  of  navigation,  ten  miles  from  Lake  Erie. 
It  was  the  center  of  an  extensive  trade  in  grain,  cooperage, 
ship-building,  etc.,  that  continued  prosperously  until  the  com- 
pletion of  the  Lake  Shore  Railway,  a  few  miles  South,  when  its 
business  rapidly  declined,  and  Milan  almost  ceased  to  exist.  Its 
name,  however,  is  now  immortal,  for  it  will  always  be  known 
as  the  birth-place  of  Thomas  Alva  Edison.  It  is  quite  befitting 
that  America  should  furnish  the  greatest  of  inventors,  and 
equally  so,  that  a  central  State,  like  Ohio,  should  include  his  vil- 
lage of  nativity.  Edison  may  be  said  to  be  the  "product"  of  a 
free  country,  and  appropriately  heads  the  longest  list  of  great 
inventors  that  history  anywhere  exhibits.  And  we  are  glad 
to  say,  like  the  ancient  Roman,  who  always  asserted  with  em- 
phasis his  Roman  citizenship,  that  Edison,  too,  rejoices  in  the 
fact  that  he  is  "an  American  citizen."  He  is  proud  of  his  na- 
tive land. 

Milan,  with  its  little  river,  surrounding  hills  and  grand  old 
forests,  salubrious  clime  and  busy  industries,  proved  an  excellent 
basis  of  physical  life  for  young  Thomas.  He  was  fond  of  the 
ramble  and  young  adventure,  and  often  indulged  in  innocent 
play  on  the  banks  of  the  Huron.  He  is  said  to  have  delighted 
in  the  construction  of  little  plank  roads,  the  excavation  of  little 
caves,  and  such  like  original  pursuits.  He  never  lacked  for 
subjects,  thus  revealing  "the  dominant  power"  very  early  in  life. 
From  the  first,  he  was  a  chubby,  rosy  faced,  laughing  boy.  He 
is  said  to  have  known  all  the  songs  of  the  canal-men  before  he 


AND  HIS  INVENTIONS.  *9 

was  five  years  old,  and  "lisped  in  homely  numbers,  'Oh,  for  a 
life  on  the  raging  canawl,'  ere  he  had  fairly  learned  his  alphabet " 
But  his  great  heritage  at  Milan  was  the  love  and  tender  solic- 
itude of  his  parents.  He  had  a  careful,  watchful  father  and  a 
loving  mother,  to  whom,  Thomas  Edison  owes  much,  if  not 
nearly  all,  that  has  made  him  great. 

His  ancestry  on  the  paternal  side  can  be  traced  back  two 
hundred  years,  when  they  were  extensive  and  prosperous  millers 
hi  Holland,  In  1 730  a  few  members  of  the  family  emigrated  to 
America. 


ceive  Forty  Spams 
milled  Dollars,  c 
Value  thereof  in 
Gold  or  Silver, 
cording  to  a  Rej 


Continental  Bill. 

Thomas  Edison,  great  grandfather  of  Thomas  Alva,  was  a 
prominent  bank  officer  on  Manhattan  Island  during  the  Revo- 
lution, and  his  name  appears  on  the  continental  money.  His 
signature  is  shown  in  the  above  engraving  on  a  continental 
note,  now  over  one  hundred  years  old.  He  died  in  the  one 
hundred  and  second  year  of  his  age.  The  race  is  remarkable 
for  its  longevity.  Thomas  Alva's  grandfather  lived  to  be  one 
hundred  and  three  yean  old. 


jo  THOMAS  A.  EDISON 

His  father,  Samuel  Edison,  is  now  living,  aged  eighty-four,  in 
perfect  health,  and  able  to  attend  to  all  the  details  of  an  ac- 
tive business  life.  He  is  six  feet  two  inches  high,  and  in  1868 
it  is  said,  "outjumped  two  hundred  and  sixty  men  belonging  to  a 
regiment  of  soldiers  stationed  at  Fort  Gratiot,  Mich." 

He  was  born  August  i6th,  1804,  in  the  town  of  Digby,  coun- 
ty of  Annapolis,  Nova  Scotia.  For]a  short  time,  and  when  quite 
young,  he  resided  at  Newark,  N.  J.,  and  subsequently,  at  the 
age  of  seven,  removed  to  the  township  of  of  Bayham,  Upper 
Canada.  He  married  Miss  Nancy  Elliott,  an  accomplished  la- 
dy of  Vienna,  Canada,  and  came  west  in  1837,  locating  at  Detroit, 
Mich.,  where  he  resided  one  year,  and  then  moved  to  Milan, 
Ohio,  and  afterwards  returned  to  Michigan  in  1854.  In  his 
younger  days  he  learned  the  tailor's  trade,  but  subsequently 
entered  commercial  life,  engaging  in  an  extensive  lumber 
business  and  afterwards  becoming  a  produce  merchant,  in  all 
which  he  has  been  sufficiently  successful  to  amply  provide  the 
comforts  of  a  happy  home.  He  has  always  been  in  good  cir- 
cumstances and  was  deeply  interested  in  the  home  education  of 
his  son,  paying  him  a  fixed  price  for  every  book  he  read  to 
encourage  him  in  the  work. 

Mrs.  Nancy  Elliott  Edison,  mother  of  T.  A.  Edison,  was  born 
in  Chenango  County,  N.  Y.,  January  roth,  1810.  She  was  of 
Scotch  and  English  parentage,  and  highly  educated.  For  seve- 
ral years  she  was  a  succesful  and  popular  teacher  in  a  Canadian 
High  School  She  died  April  gth,  1871,  but  her  memory  is  stil 
dear  to  a  long  list  of  associates,  many  of  whom  speak  of  her  as 
a  Martha  Washington.  She  was  a  fine  looking,  cultured,  well 
educated  lady,  endowed  with  great  social  powers,  and  beloved 
by  a  large  circle  of  friends.  For  her  son  Thomas  she  always 
had  the  most  tender  affection. 

Wm.  P.  Edison,  a  brother  of  Thomas  A.,  is  a  prominent  busi- 
ness man  in  Port  Huron,  Mich.,  where  he  has  resided  for  the 
last  thirty-five  years.  Samuel  Edison,  the  father,  is  also  a  resi- 
dent of  the  same  city.  A  sister,  Mrs.  Homer  Page,  is  a  resi- 
dent of  Milan,  Ohio.  This  is  the  extent  of  the  family. 


Samuel  Edison.  Mrs.  Nancy  E.  Edison, 

Parents  of  Thomas  A.  Edison. 


AND  HIS  INVENTIONS.  33 

At  the  age  of  seven  young  Edison  and  his  parents  removed 
from  Milan  to  Port  Huron,  Michigan,  where  his  father  still 
resides.  He  soon  became  reconciled  to  his  new  home,  and  was 
the  same  cheerful  lad  on  the  shores  of  the  "narrow  sea"  that  he 
had  been  on  the  banks  of  the  little  river.  The  family  residence 
at  Port  Huron  was  among  the  largest  and  finest  in  that  region 
of  country,  being  a  very  roomy,  good  old  fashioned  white  frame 
building,  located  in  the  center  of  an  extensive  grove,  and  at- 
tached to  which  was  an  observatory  giving  a  glorious  outlook 
over  the  broad  river  and  distant  hills.  How  far  this  remarkably 
pleasant  home  contributed  in  laying  the  mental  and  moral  foun- 
dations of  the  great  inventor  is  a  matter  of  mere  conjecture. 
Here,  however,  he  lived,  studying  more  or  less  for  several  years, 
at  his  mother's  side,  who  by  her  great  natural  qualifications  for 
such  a  work  and  by  a  mother's  immeasurable  love^  taught  him, 
not  only  the  "fundamental  branches,"  but  what  is  better,  the  love 
and  purpose  of  knowledge.  There  existed  an  unusual  and  su- 
perlative affection  between  the  mother  and  her  son.  She  seemed 
to  love  his  very  presence,  and  for  this  reason,  young  Thomas 
was  taught  at  home,  where  he  might  constantly  add  to  the  pa- 
rental pleasures.  It  can  be  easily  seen  how  Thomas  Edison" 
under  such  benign  and  potent  influences  became  a  well  instructed, 
and  we  may  add,  a  well  educated  boy;  for  he  was  taught  the 
presence,  power  and  possibilities  of  human  resources,  and  what 
he  himself  might  ultimately  accomplish  if  "faithful  to  the  end;" 
that  the  wide  world  was  one  great,  broad  field  of  activities,  and 
that  Nature  was  brimmed  with  law,  order,  the  beautiful  and  good. 
His  mother  taught  him  not  only  "his  alphabet,  spelling,  reading, 
writing  and  arithmetic,"  but  also  the  great  object  of  all  learning. 
She  was  careful  to  implant  the  love  of  learning  and  fire  the 
young  mind  with  a  burning  desire  to  know  more  of  the  "great 
beyond. "  In  this  she  succeeded  to  a  degree  commensurate  with 
her  efforts,  for  at  the  age^  of  ten,  young  Alva's  mind  was  an 
electric  thunder-storm  rushing  through  the  fields  of  truth.  At 
this  age  he  had  read  the  "Penny  Encyclopedias,"  "Hume's  His- 
tory of  England,"  "History  of  the  Reformation,"  "Gibbon's 
3 


34  THOMAS  A.  EDISON 

Rome, "  Sears'  "  History  of  the  World, "  several  works  on  chem 
istry  and  other  scientific  books.  He  read  them  all  with  the  ut- 
most fidelity,  never  skipping  a  word  or  formula.  It  is  this  won- 
derful habit  of  concentration,  fired  with  the  determination  to 
reach  "the  point,"  that  has  led  him  to  accomplish  so  many  as- 
tonishing results.  It  is  true  that  it  must  always  remain  a  curious 
fact  that  such  a  man  as  Mr.  Edison  should  never  have  at- 
tended the  schools,  that  his  name,  now  so  great,  was  never  en- 
rolled in  any  college  calendar,  and  that  in  fact  he  never  "went  to 
school"  more  than  two  months  in  all  his  life.  But  may  we  not, 
yea,  do  we  not,  see  again,  for  the  thousandth  time,  the  power 
and  possibilities  of  a  mother's  love  and  labor,- in  training  the  child 
in  the  way  it  should  go?  Was  not  his  home,  after  all,  his  uni- 
versity? And  was  it  not  a  good  one,  well  officered,  and  well 
adapted  to  accomplish  the  real  work?  It  is  said  his  mother  was 
a  fine  reader,  and  often  read  aloud  to  the  family.  Oh,  how  easy, 
in  this  way,  to  enkindle  an  interest,  and  impart  the  information 
that  gives  life  to  the  young  soul.  Again  we  can  trace  the  "be- 
ginnings" of  another  great  life  to  a  mother's  love.  This  was  the 
"main  battery"  that  has  sent  out,  and  still  sends  its  silent  influ- 
ence over  the  long  line  of  Edison's  life.  It  is  a  divine  adjust- 
ment, Heaven's  grand  discovery  for  man,  this  mother's  love! 
Though  gone  these  many  years,  it  is  said  Mr.  Edison  still  greatly 
reveres  his  mother's  name,  and  delights  as  her  child,  to  "rise  up 
and  call  her  blessed. " 


AND  HIS  INVENTIONS.  37 

Edison  as  "Train  Boy." 

His  SUCCESS  IN  SELLING  APPLES,  TOYS,  PERIODICALS,  ETC.,  ON  THK  TRAIN 
— How  HE  USED  THE  TELEGRAPH— HE  STARTS  A  NEWSPA- 
PER—THE EDISON  DUPLEX— His  LABORATORY  ON 
WHEELS— A  GREAT  MISHAP— YOUNG 
EDISON  PITCHED  OFF 
THE  TRAIN. 

Young  Edison  began  public  life  at  the  age  of  twelve  as  trail 
boy  on  the  Grand  Trunk  Railroad,  between  Port  Huron  and 
Detroit,  a  position  selected  by  his  father,  because  it  afforded  his 
son  an  opportunity  to  learn  many  important  lessons  in  practical 
life,  to  earn  something  of  a  livelihood,  and  to  enjoy,  still,  the 
pleasure  of  spending  many  a  pleasant  evening  at  home,  at  the 
Port  Huron  end  of  the  line.  In  this  new  vocation,  young 
Thomas  was  a  "decided  success."  He  sold  figs,  apples,  toys, 
magazines,  newspapers,  and  the  entire  inventory  of  things  that 
make  up  the  miscellaneous  merchandize  of  the  train  boy.  His 
business  rapidly  increased,  and  in  a  little  while  he  was  com- 
pelled to  employ  as  many  as  four  assistants.  For  the  purpose 
of  enlarging  his  business,  and  thus  demonstrating  his  early  gen- 
ius for  invention,  he  soon  hit  upon  the  novel  plan  of  telegraphing 
in  advance  of  his  train  the  head-lines  of  the  war  news  columns, 
which  were  properly  bulletined  at  the  stations,  and  which  caused 
his  papers  to  "go  off"  at  almost  electric  speed.  His  periodicals 
were  purchased  principally  at  the  Detroit  end  from  John  Lan- 
igan,  now  of  Chicago,  who  remembers  him  as  an  "honest  boy," 
who  did  a  "cash  business,"  but  when  "time"  was  desired,  it  was 
always  given,  and  the  "liabilities"  were  promptly  met.  His  av- 
erage daily  earnings  during  the  four  years  in  which  he  continued 
in  this  work  were  something  over  one  dollar,  aggregating  the 
neat  sum  of  nearly  two  thousand  dollars,  all  of  which  he  turned 
over  to  his  beloved  parents.  His  habits  of  study  and  love  for 
reading  followed  him  into  the  new  field,  and  led  him  in  his  early 
visits  to  Detroit  to  unite  with  the  library  association  of  that 
place.  He  undertook  the  herculean  task  of  reading  every  vol- 
ume in  that  extensive  collection.  Commencing  at  the  bottom 


38  THOMAS  A.  EDISON 

shelf,  he  actually  read  through  a  line  of  books  fifteen  feet  in 
length,  omitting  no  volume,  nor  skipping  any  part  of  a  single 
book.  The  dusty  list  included,  among  others,  Newton's  "Prin- 
cipia,"  Ure's  Scientific  Dictionaries,  Burton's  "Anatomy  of  Mel- 
ancholy," etc.  After  completing  fifteen  feet  of  the  mammoth 
project,  he  gave  up  the  job  and  thereafter  selected  more  conge- 
nial material.  He  was  an  occasional  reader  of  poetry  and  fic- 
tion. Victor  Hugo  was  among  his  favorite  authors.  The  "Les 
Miserables, "  he  read  a  dozen  times,  and  has  reviewed  it  perhaps 
as  many  times  since.  He  regards  the  "Toilers  of  the  Sea,"  by 
the  same  author,  as  a  wonderful  production.  His  memory  is 
remarkably  retentive,  and  from  his  vast  field  of  research  he  has 
always  been  able  to  make  extensive  extracts,  and  can  usually 
refer  direct  to  the  book  and  page  for  any  information  or  fact 
needed  for  experiment  and  research.  So  extensive  and  thorough 
has  been  his  earnest  reading,  that  it  is  difficult  to  mention  any 
subject  about  which  he  knows  nothing. 

While  disposing  of  his  papers  it  soon  occurred  to  young  Edi- 
son, which  is  another  demonstration  of  his  inventive  resources, 
that  he  might  as  well  get  up  a  paper  of  his  own.  Attached  to 
the  train  was  a  springless  freight  car  having  a  room  set  apart  for 
smoking  purposes,  but  which  was  so  poorly  ventilated  and  other- 
wise dilapidated  that  passengers  seldom  entered  it.  This  was 
selected  as  the  head  center  of  his  first  grand  enterprise.  Three 
hundred  pounds  of  type  were  purchased  from  the  Detroit  Free. 
Press,  and  very  soon  Edison  was  the  editor  and  publisher  of  a 
little  paper,  twelve  by  sixteen  inches,  issued  weekly,  entitled 
"The  Grand  Trunk  Herald;"  the  columns  of  which  were  devoted 
to  railway  gossip,  changes,  accidents  and  general  information. 
It  was  printed  in  the  most  primitive  style,  on  one  side  only,  the 
impressions  being  made  by  the  pressure  of  the  hand.  It  sold 
for  three  cents  a  copy,  and  reached  a  circulation  of  several  hun- 
dred. On  one  occasion  it  came  under  the  eye  of  the  celebrated 
English  engineer,  George  Stephenson,  builder  of  the  great  tu- 
bular bridge  at  Montreal,  who  at  once  ordered  an  extra  edition 
for  his  own  use.  It  numbered  among  its  contributors  many 


Printing  The  Grand  Trunk  Herald  on  the  Train. 


AND  HIS  INVENTIONS.  41 

worthy  railroad  men,  and  became  quite  celebrated  as  the  only 
journal  in  the  world  printed  on  a  railway  train.  Among  its  co- 
temporaries  in  which  it  received  favorable  mention,  was  num- 
bered the  London  Times.  Edison  was  highly  delighted  with,  the 
new  enterprise,  and  became  in  fact,  a  little  Ben.  Franklin,  whose 
early  history  in  this  line,  and  ultimate  success  as  an  influential 
man  doubtless  greatly  inspired  the  young  editor  of  the  Herald. 

Parallel  with  this  novel  enterprise  and  in  the  same  old  aban- 
doned freight  car,  Thomas  Alva  was  prosecuting  another  and 
entirely  different  line  of  labor.  From  the  very  start  he  was  a 
self-exhibition  of  the  duplex  system,  which  long  afterwards  ap- 
peared through  his  manipulations,  in  telegraphy.  He  procured 
a  work  on  chemistry — Freseniu's  Qualitative  Analysis — pur- 
chased a  supply  of  chemicals  on  the  instalment  plan,  obtained 
some  retort  stands  from  the  men  in  the  railroad  shops  in  ex- 
change for  papers,  and  opened  a  laboratory.  This  was  his  first 
effort  in  the  great  world  of  chemical  law.  He  saw  at  once  the 
wonderful  and  varied  attributes  of  material  things;  the  endless 
existing  affinities,  and  occult  power  and  possibilities  of  the  ele- 
ments. It  was  a  new  world  in  which  he  stood  entranced.  And 
from  that  time,  on  to  the  present,  he  has  never  ceased  to  delve 
into  the  subtle  influence  and  mysteries  of  chemical  science. 
The  laboratory  of  the  abandoned  smoking  car  and  the  labora- 
tory on  the  hill  at  Menlo  Park  are  in  the  same  series.  The  real 
difference  is  simply  a  matter  of  wheels,  which  persisted  in  car. 
rying  the  former  at  the  rate  of  thirty  miles  an  hour,  jostling  and 
bumping  and  otherwise  seriously  interfering  with  the  young 
chemist's  experiments,  while  the  latter  stands  stock-still  at  Menlo 
Park,  and  allows  the  distant  whispers  to  jingle  against  the  car- 
bon button,  or  permits  the  heat  from  the  North  Star  whose  light 
has  been  forty-seven  years  in  reaching  the  earth  at  the  rate  of  one 
hundred  and  eighty-four  thousand  miles  per  second,  to  quietly 
register  itself  on  the  scale  of  the  tasimeter.  Nevertheless,  this 
difference  of  wheels  ultimately  proved  a  serious  matter  for  young 
Edison.  In  this  rudely  constructed  laboratory  there  was  a  bottle 
of  phosphorus,  from  which  one  day  the  water  had  evaporated, 


4»  THOMAS  A.  EDISON 

and  which  an  extra  jolt  of  the  springless  car  tumbled  to  the 
floor.  A  scene  of  confusion,  of  course,  followed.  The  car  was 
ignited  and  a  conflagration  was  imminent.  The  conductor 
rushed  hurriedly,  and  we  may  add  madly,  to  the  scene  of  conflict 
and  with  difficulty  extinguished  the  flames.  In  his  rashness,  and 
to  make  it  absolutely  certain  that  such  an  event  could  not  pos- 
sibly occur  again,  he  unceremoniouly  threw  overboard,  not  only 
the  chemicals  of  the  entire  laboratory,  but  also  the  printing 
establishment,  and  closed  the  fearful  drama  by  soundly  boxing 
young  Edison's  ears,  and  hurriedly  ejecting  him  from  the 
blazing  train.  What  has  become  of  this  impetuous  gentle- 
man, we  do  not  know.  Perhaps  he  is  endeavoring  to  atone 
for  his  work  as  the  gentlemanly  conductor  of  the  excursion 
trains,  which,  now  and  then,  to  accommodate  scientists,  friends 
and  the  curious,  run  from  Boston  to  Menlo  Park.  Sad  as  was 
the  event,  it  did  not,  however,  discourage  the  young  chemist  and 
editor.  He  doubtless  realized  the  importance  of  fire-proof 
smoking  cars,  and,  if  he  had  felt  more  amiable,  at  the  time, 
towards  railway  officials,  might  have  invented  one,  but  in  lieu 
of  this,  and  with  a  better  knowledge  of  phosphorus  and  human 
nature,  he  gathered  up  his  scattered  materials  and  located  in 
what  he  deemed  a  much  safer  place,  the  basement  of  his  father's 
residence  at  Port  Huron.  Here,  as  opportunity  afforded,  he 
continued  his  experiments  in  chemistry,  and,  in  time,  issued  an- 
other petite  journal  entitled  "  Paul  Pry, "  which  was  more  after  the 
regular  plan  of  a  newspaper,  and  every  way  an  improvement  on 
the  "Herald. " 

It  had  a  host  of  contributors  and  a  long  list  of  subscribers. 
But  alas  for  all  sublunary  affairs.  It  was  not  long  before  an  ar- 
ticle from  a  contributor  appeared  in  the  columns  of  this  news- 
paper which,  though  Edison  persistently  claimed  was  not  within 
the  bounds  of  the  legally  libelous,  yet  gave  great  offence  to  a 
subscriber  who  at  once  sought  the  editor  in  chief,  and  finding 
him  on  the  margin  of  the  St.  Clair,  deliberately  picked  him 
up  and  pitched  him  into  the  river.  It  was  an  unexpected  and 
hasty  plunge  bath,  entirely  involuntary  on  the  part  of  young 


Edison  Pitched  into  the  River. 


AND  HIS  INVENTIONS.  45 

Thomas,  but  from  which  he  soon  emerged,  safe  and  sound,  with 
the  conviction,  however,  not  soon  forgotten,  that  the  life  of  an 
editor  is  environed  with  no  inconsiderable  degree  of  danger.  In 
the  former  great  mishap  fire  was  the  essential  factor;  in  the  latter 
it  was  water !  Thus  early  in  life,  and  in  a  peculiar  manner,  was 
the  great  inventor  baptized  with  the  two  great  elements.  Nor 
was  it  an  ordinary  "sprinkle"  either;  in  both  instances  it  was  a 
rousing  "immersion!" 

Mr.  Edison  occasionally  refers  to  this  train  boy  .  period  of  his 
life,  and  always  with  much  humor.  When  asked  one  day  if  he 
belonged  to  the  class  of  train  boys  "who  sell  figs  in  boxes  with 
bottoms  half  an  inch  thick?"  he  responded  with  a  merry  twinkle, 
"If  I  recollect  right  the  bottoms  of  my  boxes  were  a  good  inch." 
A  daguerreotype  of  his  train  boy  epoch  is  yet  extant,  which  rep- 
resents the  great  inventor  as  a  chubby  faced  boy  in  glazed  cap 
and,  with  a  bundle  of  papers  under  his  arm.  His  lips  are 
wreathed  in  smiles,  and  altogether  he  presents  the  appearance  of 
a  contented  and  happy  little  fellow.  Such  a  life  had,  of  course, 
its  ups  and  downs,  but  after  all,  it  was  a  profitable  schooling  for 
young  Edison.  Besides,  during  the  four  years  he  continued  in 
this  work  he  was  always  in  daily  reach  of  home,  where  his  sor- 
rows as  well  as  joys  were  promptly  shared  by  those  who  could 
easily  and  gladly  impart  the  essential  lesson.  The  easy  manner 
in  which  he  disposed  of  his  limited  stock  of  merchandize,  the 
use  of  the  telegraph  to  aid  in  the  disposal  of  his  papers,  the  suc- 
cessful issuing  of  a  weekly  paper,  the  laboratory  with  its  varied 
experiments,  and  the  wonderful  amount  of  solid  reading  that  per- 
vaded  all,  clearly  demonstrate  that  Mr.  Edison  at  this  age  was 
not  only  a  most  extraordinary  "train  boy,"  but  also  aremaikable 
genius.  The  spirit  of  invention  was  upon  him.  The  click  of 
the  "sounder"  w*s  audible,  and  the  "message"  of  his  coming 
greatness  was  on  its  way. 


46  THOMAS  A.  EDISO* 

Early   Reminiscences. 

Mr.  Samuel  Edison  states  that  his  son,  T.  A.  E.,  never  had 
any  "boyhood  days"  in  the  common  acceptation  of  that  term. — 
From  the  first  his  inclinations  were  in  the  direction  of  machinery, 
and  amusements,  with  steam  engines  and  various  mechanisms. 
It  is  not  surprising  therefore  to  find  him  at  an  early  age  perfect- 
ing, on  a  small  scale,  a  working  engine.  When  on  the  Grand 
Trunk  line  he  frequently  rode  with  the  engineer  that  he  might 
learn  something  about  the  mysteries  of  a  locomotive,  and  on 
one  occasion,  to  demonstrate  his  proficiency,  while  the  engineer 
was  asleep,  ran  a  train  nearly  the  entire  trip,  with  the  only 
mishap  of  pumping  too  great  a  quantity  of  water  into  the  boiler, 
which  being  thrown  from  the  smoke-stack  deluged  the  engine 
with  filth.  Occasionally,  as  he  had  opportunity,  he  would  visit 
the  railroad  machine  shops,  where  he  always  manifested  the 
greatest  interest  in  examining  the  machinery. 

He  was  always  careful  with  his  little  labratory  and  would  not 
allow  his  things  to  be  tampered  with  by  any  one.  To  insure 
better  safety  he  labeled  every  bottle  in  the  establishment 
"poison." 

When  excited,  young  Thomas  was  slow  to  cool  down.  The 
sequel  to  the  dreadful  cold  water  catastrophe,  was  that  the  name 
of  the  person — J.  H.  B.  of  Port  Huron — who  threw  him  into  the 
river,  was  studiously  kept  out  of  the  columns  of  Paul  Pry.  If 
Thomas  had  not  been  a  good  swimmer,  that  occasion  might  have 
been  far  more  serious  than  it  was. 

Edison's  sister  tells  a  good  story  of  his  childhood:  "He 
tried  to  sit  on  eggs,"  she  said.  "What  do  you  mean?"  inquired 
the  listener.  "Why,  he  was  about  six  years  old,  I  should  think, 
and  he  found  out  how  the  goose  was  sitting,  and  then  saw  what 
the  surprising  result  was.  One  day  we  missed  him,  called,  sent 
messengers,  and  couldn't  find  him  anywhere.  By  and  by,  don't 
you  think,  father  found  him  curled  up  in  a  nest  he  had  made 
in  the  barn  and  filled  with  goose  eggs  and  hen's  eggs, — actually 
sitting  on  the  eggs  and  trying  to  hatch  them. " 


AND  HIS  INVENTIONS.  47 

The  Young  Electrician. 

HB  BUYS  A  BOOK  ON  ELECTRICITY — EXTEMPORIZES  A  SHORT  LINE — THE 
TOM-CAT   ELECTRICAL-BATTERY— A  DARING  FEAT  IN    FRONT 
OF  A  LOCOMOTIVE— THE  YOUNG  SON  OF  THUNDER  GET- 
TING DOWN  TO  BUSINESS— ANECDOTES. 

Edison's  interest  in  telegraphy  dates  from  the  time  when,  as 
train  boy,  he  sent  the  head  lines  of  the  war  news  columns  over 
the  wires  in  advance  of  his  trains  to  be  bulletined  at  the  stations. 
In  this  novel  and  sucessful  plan  he  saw  at  once  the  great  advan- 
tages of  the  telegraph  system,  and  made  up  his  mind  that  he 
would  very  soon  know  more  about  it.  He  immediately  pur- 
chased a  standard  work  on  the  electric  telegraph,  and  began  its 
careful  persual.  Every  day  led  him  farther  out  into  the  exciting 
wonders  of  electrical  science.  He  was  pleased,  delighted  and 
amazed.  A  new  world  was  discovered,  marvelous  and  grand. 
An  apocryphal  power  silently  stole  out  from  the  acidulated 
metals  and  leaped  two  thousand  miles  per  second.  It  laughed 
at  space  and  time.  There  were  things  it  seemed  to  love  and 
things  it  hated,  things  to  which  it  clung  and  things  it  would  not 
touch.  Now  like  the  light  of  the  sun,  then  silent  and  dark,  yet 
ever  moving,  and  exerting  its  strange  incomprehensible  force. 
Easily  could  he  see  the  cup,  the  copper,  zinc  and  acid,  and 
could  hear  the  click  of  the  sounder;  but  from  whence  and  how 
comes  this  influence?  That  was  the  question.  He  studies  the 
chemistries  of  the  battery,  and  delves  farther  into  his  work  on 
electricity.  He  concedes  the  wonders,  but  exclaims,  "what  I 
know  not  now,  I  may  know  hereafter. " 

It  is  under  the  conviction  of  this  final  exclamation  that  young 
Edison  passes  from  the  more  theoretical  into  practical  telegraphy. 
A  short  line  is  extemporized,  connecting  his  new  basement  of- 
fice at  home  with  the  residence  of  his  young  assistant,  James 
Ward,  also  of  Port  Huron.  In  its  construction  they  used  com- 
mon stove  pipe  wire,  insulated  with  bottles  placed  on  nails 
driven  into  trees,  and  crossed  under  an  exposed  road  by  means 
of  a  piece  of  an  abandoned  cable  captured  from  the  Detroit 


48  THOMAS  A.  EDISON 

river.  The  magnets  used  in  connection  with  this  primitive  line 
were  made  of  old  wire  wound  with  rags  for  insulation,  while  a 
piece  of  spring  brass  formed  the  all  important  key.  It  is  said 
that  these  two  young  aspiring  electricians,  now  the  proprietors 
of  a  "short  line"  and  evidently  in  high  glee,  "were  somewhat 
mixed  as  to  the  relative  value  of  dynamic  and  static  electricity 
for  telegraphic  purposes  and  the  first  attempt  to  generate  a  cur- 
rent was  by  means  of  a  couple  of  huge  cats  rubbed  vigorously 
at  each  end  of  the  line  at  an  appointed  time. "  The  only  suc- 
cess attending  this  novel  and  gigantic  effort  was  the  complete 
and  hurried  riddance  of  the  two  great  cats  which,  under  the 
pressure  of  the  moment,  lit  out  at  lightning  speed  and  were  never 
heard  of  afterwards.  Had  the  "ground  wire"  in  this  case  been 
properly  adjusted,  that  is  wound  securely  about  the  necks  of  the 
feline  batteries,  this  unexpected  phenomenon  might  have  been 
avoided,  and  better  success,  have  followed. 

Mr.  Reid  in  his  "Memorial  Volume,  referring  to  this  incident, 
says: 

"He  had  seen  sparks  emitted  from  a  cat's  back.  Judging  that 
there  must  be  good  battery  where  the  indications  were  so  strong, 
he  inserted  a  tom-cat  in  the  circuit,  using  the  fore  and  hind  feet 
as  electrodes.  The  connections,  after  some  resistance,  having 
been  duly  made,  he  tried  to  start  an  induced  current  by  rubbing 
the  cat's  back,  the  incensed  feline  meanwhile  giving  him  some 
forced  telephone  lessons,  and  in  other  ways  objecting  to  his 
electrocratical  operations.  The  experiment  however  was  not 
without  success.  A  tremendous  local  current  and  perfect  elec- 
tric arc  was  produced,  but  it  would  not  work  the  line,  and  was 
abandoned.  The  experiment  illustrated  the  humor  of  the  man." 

Had  young  Thomas  and  James  demonstrated  the  feasibili- 
ty of  cats  for  electrical  purposes  they  would  doubtless  have 
received  the  homage  of  mankind.  Long  after  this  amusing 
event,  Mr.  Edison  was  forcibly  reminded  of  the  great  leap  made 
by  his  cat  on  this  occasion,  when  he  discovered  what  he  be- 
lieved then  and  still  believes,  to  be  a  "new  kind  of  electricity," 
which  is  capable  of  causing  a  spark  "to  leap  twenty  feet  in  the 


The  Cat  Battery  Experiment. 


YounP  FHison  Rescuing  a  Child 


AND  HIS  INVENTIONS.  51 

clear  air"  without  effecting  in  the  least  manner  the  galvanometer. 

Soon  after  this  experiment,  in  nowise  discouraged,  some  old 
telegraph  instruments  and  battery  materials  were  purchased  and 
a  successful  short  line  was  established,  which  at  that  time  was 
quite  an  achievement^  it  being  among  the  first  of  the  kind  ever 
inaugurated.  In  a  boy-like  way  his  aspirations  seemed  now 
crowned  with  success.  He  was  not  only  an  electrician,  but  had 
constructed  a  telegraph  line  of  which  he  was  at  once  Superin- 
tendent, proprietor  and  operator.  Whether  he  posted  up  his 
"Rules  and  Regulations,"  scheduled  his  "rates"  and  forwarded 
night  messages  at  halt  price,  etc.,  is  not  known,  but  it  is  quite 
likely  something  of  this  kind  was  done.  All  this  however 
was  but  a  high  order  of  boyish  sport;  a  toying  with  heaven's 
lightning,  and  yet  beneath  it  is  the  impulse  to  more  real  and 
grand  achievements. 

The  quadruplex,  electro-motograph,  phonograph,  telephone, 
etc.,  were  all  here  in  germinal  form  and  within  microscopic  range. 
At  the  end  of  the  "short  line,"  sat  the  young  son  of  thunder, 
with  a  hand  upon  a  rustic  and  slow  moving  key,  that  was  des- 
tined to  fashion  another  and  better  line  and  mechanism  that 
should  pick  up  three  thousand  and  one  hundred  full  words  in  a 
single  minute! 

Soon  after  this  an  event  occurred  that  proved  a  turning  point 
in  Edison's  life.  It  was  a  daring,  but  successful  effort  made  to 
rescue  the  life  of  a  little  child.  J.  A.  Mackenzie,  station  agent 
and  operator  at  Mt.  Clemens,  near  Port  Huron,  had  a  dear  little 
boy  only  two  years  old,  which  one  day  crept  on  the  track  just 
in  tront  of  a  rushing  train.  A  moment  more  and  its  mangled 
form  would  have  been  quivering  in  the  dust.  Young  Edison 
saw  the  impending  danger.  He  flew  to  the  rescue  and  at  the 
point  of  his  own  life,  rescued  the  child.  It  was  a  noble  deed, 
and  out  of  gratitude,  the  father,  volunteered  to  teach  young 
Edison  how  to  become  an  operator. 

This  offer  was  gladly  accepted  and  thereafter  Thomas  Alva, 
after  reaching  Port  Huron  would  return  by  freight  train  to  Mt 
Clemens  in  order  to  learn,  at  night,  the  lessons  that  were  to 


S2  THOMAS  A.  EDISON 

perfect  him  in  his  newly  chosen  and  interesting  employment 

A  warm  friendship  existed  from  the  first,  between  Mr.  Mac- 
kenzie, the  teacher,  and  young  Edison,  the  pupil,  which  to  this 
day  continues,  though  we  believe  now,  Mr.  Edison  is  the  teach- 
er. It  was  with  Mr.  Mackenzie  and  at»Menlo  Park  that  Mr. 
Edison,  only  a  few  day's  since,  perpetrated  a  little  pleasantry. 

"Look  here"  says  Edison,  "I  am  able  to  send  a  message  from 
New  York  to  Boston  without  any  wire  at  all. " 

That  is  impossible,  says  Mackenzie. 

Oh,  no  1  says  Edison.     Its  a  new  invention, 

Well,  how  is  it  done,  All  says  Mack. 

By  sealing  it  up  and  sending  by  Mail  1 1 

The  old  gentleman  laughed  heartily  at  the  joke. 


A 

B 

C 

D 

E 

F 

G 

H 

I 

J 

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L 

M 

N 

0 

P 

Q 

R 

S 

T 

U 

V 

w 

X               Y 

Z 

& 

NUMERALS. 

I 

a 

3 

4 

5 

PUNCTUATION  MARKS. 

Period.  Comma.  Semi-colon.  Quotation. 

Parenthesis.  Interrogation.  Italics.  Paragraph. 

Exclamation, 


AND  HIS  INVENTIONS.  53 

The  Young  Operator. 

His  ENGAGEMENT  AT  PORT  HURON— RESIGNS— GOES  TO  STRATFORD — 
RIGS  AN  INGENIOUS  MACHINE — TELEGRAPHING  BY  STEAM! 

Edison  was  yet  a  boy,  being  only  fifteen  years  of  age.  But 
in  five  months  after  he  began  taking  lessons  of  Mr.  Mackenzie 
at  Mt.  Clemens,  he  was  sufficiently  advanced  in  the  art  of 
sending  messages  to  procure  employment  in  the  telegraph  office 
at  Port  Huron.  The  salary  was  $25.00  per  month,  with  the 
understanding  that  he  should  have  extra  pay  for  extra  work. 
The  office  was  in  a  jewelry  store  and,  as  usual,  Edison  indulged 
in  his  mechanical  inclinations.  He  worked,  however,  very  in- 
dustriously at  the  key,  night  and  day,  that  he  might  improve 
himself  as  an  operator. 

After  six  months  of  hard  labor,  on  finding  his  pay  for  extra 
work,  witheld,  he  at  once  resigned,  and  left  Port  Huron,  for 
Stratford,  Canada,  where  he  engaged  as  night  operator.  Here 
he  applied  his  ingenuity  in  a  novel  way,  which  shows  at  least, 
how  fertile  must  have  been  the  young  operator's  brain.  The 
operators  were  required  to  report  "six"  every  half  hour  to  the 
Circuit  Manager.  Young  Thomas  instead  of  reporting,  in 
person,  rigged  a  wheel  with  Morse  characters  cut  in  the  circum- 
ference in  such  a  way  that  when  turned  by  a  crank  it  would 
write  the  figure  "six"  and  sign  his  office  call.  The  watchman 
turned  this  wheel  while  Edison  slept. 

His  stay  at  this  point  was  brief.  One  night  the  dispatcher 
sent  an  order  to  hold  a  train.  Edison  repeated  back  the  mes- 
sage before  showing  it  to  the  conductor.  When  he  ran  out  for 
the  purpose  the  train  had  pulled  off  from  the  side-track  and  was 
gone.  When  the  dispatcher  was  notified,  the  opposing  train 
was  beyond  reach.  Fortunately  the  two  trains  met  on  a  straight 
track  and  no  accident  happened.  The  railroad  Superintendent 
sent  for  Edison  and  so  frightened  him  with  threats  of  imprison- 
ment that,  without  getting  his  wardrobe,  he  started  for  home, 
and  was  greatly  delighted  to  reach  his  native  land. 

His  ready  ingenuity  was  shown  in  an  early  instance  of  facile 


54  THOMAS  A.  EDISON 

adaptation  of  the  processes  of  his  new  profession  to  novel  circum- 
stances. One  day  an  ice-jam  broke  trie  cable  between  Port 
Huron  in  Michigan  and  Sarnia  on  the  Canada  side  and  stopped 
communications.  The  river  is  a  mile  and  a  half  wide.  It  was 
impassible  and  no  present  means  existed  of  repairing  it.  Young 
Edison  jumped  upon  a  locomotive  and  seized  the  valve  con- 
trolling the  whistle.  He  had  an  idea  that  the  scream  of  the 
whistle  might  be  broken  into  long  and  short  notes,  correspond- 
ing to  the  dots  and  dashes  of  telegraphing. 

The  whistle  sounded  over  the  waters :  Toot,  toot,  toot,  toot — 
toot,  toooot — toooooot — toooooot — toot-toot — toot-toot. 

" Halloo!  Sarnia!    Do  you  get  me?" 

"Do  you  hear  what  I  say?" 

No  answer. 

"Do  you  hear  what  I  say,  Sarnia?" 

A  third,  fourth  and  fifth  time  the  message  went  across  without 
response,  but  finally  the  idea  was  caught  by  an  operator  on  the 
other  side;  answering  toots  came  cheerfully  back,  and  the  con- 
nection was  again  established.  This  novel  incident  was  a 
feather  in  young  Edison's  cap  and  his  praises  were  sounded 
abroad. 

He  spent  a  few  weeks  at  Port  Huron  in  study,  but  operators 
were  in  demand,  and  he  obtained  a  situation  at  Adrian,  Mich. 
Here  he  had  a  small  shop  and  a  few  tools,  where  his  spare  time 
'was  used  in  repairing  instruments  and  making  such  experiments 
as  he  had  the  means  to  accomplish.  It  was  then  a  peculiarity 
of  the  Morse  telegraph  system  that  only  one  message  at  a  time 
could  be  sent  on  a  wire.  On  one  occasion  when  he  had  some 
message  from  the  Superintendent  he  insisted  on  taking  the  line 
from  all  comers.  The  Superintendent  of  Telegraph  lived  in  the 
same  town  and  had  an  instrument  in  his  house.  Hearing  the 
tussel  on  the  wire,  he  rushed  to  the  office,  pounced  upon  young 
Edison,  and  discharged  him  for  violation  of  rules.  He,  however, 
at  once  found  a  position  as  night  operator  in  Fort  Wayne  where 
he  made  rapid  progress  in  his  work  and  in  two  months  was  en- 
engaged  at  Indianapolis. 


Edison  Telegraphing  by  Steam. 


56  THOMAS  A.  EDISON 

The  Young  Inventor  and  Operator. 

INVENTS  AN  INSTRUMENT— TELLS  THE  BOYS  TO  "  RUSH  HIM  " — FIDELITY 

REWARDED — BECOMES  A  FIRST  CLASS 

OPERATOR. 

While  operating  at  Indianapolis,  young  Edison  invented  his 
first  successful  telegraph  instrument  It  was  an  automatic  re- 
peater which  transferred  the  writing  from  one  telegraph  line  into 
another  line  without  the  medium  of  a  sending  or  receiving  operator. 
It  was  considered  an  important  achievement  for  one  so  young 
and  is  described  in  a  recent  work  on  telegraphy,  as  "probably  the 
most  simple  and  ingenious  arrangement  of  connections  for  a 
repeater  known,  and  has  been  found  to  work  well  in  practice. 
It  is  especially  good  and  convenient  where  it  is  necessary  to  fit 
up  a  repeater,  in  an  emergency,  with  ordinary  office  instru- 
ments. " 

Edison's  ambition  as  an  operator  was,  like  that  of  most  opera- 
tors, to  be  able  to  take  what  is  called  "press  report."  To  accom- 
plish this  end  he  practiced  at  night  incessantly  and  was  finally 
awarded  a  trial,  but  finding  himself  making  too  many  "breaks," 
or  interrogations,  he  adjusted  two  more  recording  registers, 
one  to  receive  and  the  other  to  repeat  the  embossed  writing  at 
-slower  speed,  so  it  could  be  copied.  When  this  new  arrange- 
ment was  properly  adjusted,  young  Edison  felt  very  secure  and 
at  once  announced  to  the  sending  operator  to  "rush  him. "  This 
gave  him  a  brief  reputation  as  a  receiving  operator,  but,  alas  for 
the  press  reports,  they  came  in  too  slowly,  which  caused  com- 
plaint and  he  was  suspended  from  the  work  and  afterwards  trans- 
ferred to  Cincinnati. 

Here  he  worked  a  day  wire  and  continued  to  practice  at 
night,  always  "subbing"  for  the  night  men  whenever  he  could  get 
the  privilege.  His  fidelity  and  industry  were  finally  rewarded  in 
this  city  and  in  the  following  manner. 

After  he  had  been  in  Cincinnati  three  months  a  delegation  of 
Cleveland  operators  came  down  to  organize  a  branch  of  the 
Telegraphers'  Union,  which  resulted  in  a  great  strike  among 


AND  HIS  INVENTIONS.  57 

the  operators.  They  struck  the  office  in  the  evening,  and  the 
whole  force,  with  one  exception,  went  off  on  a  gigantic  spree. 
Edison  came  round  as  usual  to  practice,  and  finding  the  office  so 
nearly  deserted  took  the  press  report  to  the  best  of  his  ability, 
and  worked  through  the  night,  clearing  up  business.  The  fol- 
lowing day  he  was  rewarded  by  an  increase  of  salary,  from  $65 
to  $105  per  month,  and  was  given  the  Louisville  wire,  one  of 
the  most  desirable  in  the  office.  Mr.  R.  Martin,  known  among 
the  craft  as  "  Bob  Martin, "  one  of  the  fastest  senders  in  the 
country,  worked  the  Louisville  end,  and  from  the  experience 
here  acquired,  Edison  dates  his  ability  as  a  first-class  operator. 

Young  Edison's  ambition,  however,  was  not  at  rest  when  he 
found  that  he  could  jingle  the  key  as  rapidly  as  Bob  Martin. 
Beyond  this  were  higher  aims  of  which  Bob  never  dreamed  and, 
which  so  wholly  absorbed  Edison's  mind  that  it  not  unfrequently 
was  the  cause  of  apparent  neglect  in  what,  to  the  average  mind, 
seemed  very  essential.  He  had  already  invented  his  automatic 
repeater,  but  he  saw  other  principles  possible  to  be  utilized  and 
these  occupied  his  mind.  He  cared  little  for  dress  and  was 
willing  to  work  at  all  hours,  night  or  day,  but  he  would  not  relin- 
quish his  efforts  to  solve  what  appeared  to  his  companions,  utter 
impossibilities.  These  efforts  were  rewarded  by  the  production 
of  a  remarkable  steam  engine  and  the  discovery  of  his  duplex 
transmission  basis. 

So  intensely  did  these  points  occupy  his  mind  and  so  positive 
was  he  of  duplex  transmission  and  other  possibilities  of  great 
importance  in  telegraphy,  and  which  long  ago  he  has  made  prac- 
tical, that  his  companions  dubbed  him  with  the  title  of  "luny, " 
or  crazy  man,  a  name  which  clung  to  him  for  years.  But  other 
good  men  had  been  served  in  the  same  manner  and  he  was  not 
discouraged.  Notwithstanding  this  insulting  title  Edison  had 
the  good  will  of  his  associates.  He  continued  his  extensive  re- 
search and  reading,  and  as  opportunity  afforded,  indulged  in  such 
experiments  as  tended  to  demonstrate  his  convictions  in  electri- 
cal science. 


5*  THOMAS  A.  EDISON 

Edison's  Ups  and  Downs. 

THE  INVENTOR  vs.  THE  OPERATOR — THUNDER  ALL  ROUND  THE  HORIZON 

— FOOTING  IT  IN  TENNESSEE — OFF  FOR  SOUTH  AMERICA — 

"  RUN  "  ON  A  BANK— INCIDENTS. — 

In  1 864,  .young  Edison  went  to  Memphis  where  he  obtained  a 
more  remunerative  salary.  But  his  associates  were  dissolute  and 
imposed  upon  his  good  nature  to  such  an  extent  that  the  work 
he  did  was  enormous.  Abstemious  himself  almost  to  stoicism, 
he  freely  loaned  his  money  to  his  companions  or  expended  it  in 
the  purchase  of  books  and  apparatus.  While  here,  and  still  but 
a  boy  of  seventeen,  he  made  and  put  into  operation  his  auto- 
matic repeater,  so  that  Louisville  and  New  Orleans  could  work 
direct,  thus  saving  the  work  of  one  operator  and  receiving  a 
compliment  for  his  ingenuity. 

The  idea  of  duplex  transmission  had  taken  possession  of  him, 
and  he  was  perpetually  advocating  and  experimenting  to  ac- 
complish it.  These  efforts  were  looked  upon  with  disfavor  by 
the  management,  and  in  the  changes  resulting  upon  the  transfer 
of  the  lines  from  the  Government  to  the  Telegraph  Company 
Edison  was  dismissed. 

Being  without  money,  and  having  transportation  to  Decatur 
only,  he  walked  to  Nashville,  where  William  Foley,  an  operator 
in  the  same  predicament,  was  found,  and  they  traveled  together 
to  Louisville.  Edison  had  only  a  linen  suit,  and  on  arriving  at 
Louisville  he  found  the  weather  extremely  chilly.  He  hunted 
up  a  friend  who  loaned  him  money  for  his  immediate  need. 
Foley's  reputation,  it  is  said  was  too  bad  to  obtain  a  situation  for 
himself,  but  he  recommended  Edison,  who  obtained  work.  For 
this  service  Edison  supported  Foley  till  he  could  get  employ- 
ment. 

Edison  describes  the  Louisville  office  at  this  time  as  a  fearful 
place.  Rats  in  great  numbers  kept  the  operator  company  at 
night.  The  discipline  was  lax  in  all  things  except  the  quality 
and  promptness  of  work.  Edison  was  required  to  take  reports 
on  a  line  worked  on  the  blind  side  of  a  repeater,  where  he  had 


AND  HIS  INVENTIONS.  59 

no  chance  to  break.  This  required  skill,  and  he  attained  to  a 
rare  perfection  by  the  most  careful  study  of  names,  markets,  and 
general  information. 

The  line  was  old  and  in  poor  condition,  being  subject  to  many 
interruptions  and  changes.  To  assist  in  his  work,  Edison  was  in 
the  habit  of  arranging  three  sets  of  instruments,  each  with  a 
different  adjustment,  so  that  whether  the  circuit  was  strong  or 
weak,  or  no  matter  how  rapid  the  change,  he  was  able  to  receive 
the  signals  accurately.  He  remained  in  Louisville  for  nearly 
two  yeajs  and  then,  owing  to  glowing  reports  which  he  had 
heard,  made  up  his  mind  he  would  go  to  South  America. 

Economy  was  now  rigid,  and  funds  sufficient,  were  soon  amass- 
ed for  the  grand  departure.  In  connection  with  two  of  his  as- 
sociates, Messrs  Keen  &  Warren,  they  finally  started  for  the 
southern  clime  via  New  Orleans.  On  arriving  at  the  latter 
place,  the  vessel  upon  which  they  were  to  ship  had  fortunately 
sailed.  By  a  fortuitous  circumstance,  Edison  fell  in  with  a 
Spaniard  who  had  traveled  all  around  the  world.  He  told  the 
young  adventurer  that  of  all  the  countries  he  had  ever  visited, 
the  United  States  was  the  best,  having  the  most  desirable 
government,  institutions,  climate,  and  people.  This  wholesome 
advice  shook  Edison's  determination,  and  in  connection  with 
his  disappointment,  and  delay,  he  resolved  to  go  home.  So  he 
returned  to  Port  Huron,  via  the  Gulf  and  Atlantic  States. 
After  a  pleasant  visit  among  his  relatives  and  friends  Edison  re- 
turned to  Louisville,  where  he  was  again  employed  as  an  opera- 
tor. 

He  now  began  work  with  renewed  vigor  and  determination, 
saving  his  daily  earnings  to  invest  in  additions  to  his  library, 
apparatus,  printing  office  and  shop.  New  life  was  infused  into 
all  these  departments  and  in  a  short  time  he  had  prepared  a 
volume  on  electricity  which  he  proposed  to  issue  from  his  own 
office,  but  the  undertaking  was  too  great  for  his  limited  facilities. 

He  went  into  a  most  elaborate  series  of  experiments,  as  was 
his  custom  when  investigating  any  subject,  to  determine  the 
most  rapid  and  best-adapted  style  of  penmanship  for  an  opera- 


60  THOMAS  A. 

tor's  use.  He  finally  fixed  upon  a  slightly  back-hand,  with 
regular  round  characters,  isolating  the  letters  from  each  other, 
and  without  shading.  This  beautiful  penmanship  he  became 
able  to  produce  at  the  speed  of  forty-five  words  per  minute, 
which  is  the  extreme  limit  of  a  Morse  operator's  ability  to 
transmit.  A  specimen  of  his  penmanship  is  seen  in  Mr.  Edison's 
autograph  in  the  frontis-piece.  Edison's  description  of  the  habits 
of  his  associate  operators  at  this  time  is  amusing  in  the  extreme. 
Often  when  he  went  home  from  his  work  in  the  small  hours  of 
the  morning  he  would  find  three  of  the  boys  on  his  bed  with 
their  boots,  where  they  had  crawled  after  an  evening's  dissipa- 
tion. He  would  gently  haul  them  out  and  deposit  them  on  the 
floor,  while  he  turned  in  to  sleep. 

During  young  Edison's  stay  in  Louisville  the  telegraph  office 
was  removed  to  a  building,  fitted  up  with  improved  fixtures. 
The  instruments,  which  in  the  old  office  were  portable,  in  the 
new,  were  fastened  down  to  tables  and  strict  orders  were  issued 
from  the  proper  authorities  not  to  move  a  single  instrument. 
This  order  not  only  interfered  with  Edison's  convenience  in  tak- 
ing reports,  but  also  seriously  discommoded  him  in  his  experi- 
ments. He  could  not  desist,  and  three  sets  of  instruments  were 
readjusted,  so  as  to  aid  him  in  taking  reports,  and  on  one 
occasion  he  took  every  instrument  out  of  the  office  for  the 
purpose  of  trying  an  experiment. 

Directly  beneath  the  new  telegraph  office  were  elegantly 
furnished  banking  rooms,  the  private  office  of  which  was  under 
the  batiery  room.  This  was  richly  carpeted.  One  night  in 
trying  to  abstract  some  sulphuric  acid  for  experimental  purposes 
he  tipped  over  the  whole  carboy.  The  acid  ran  through  the 
floor  and  ceiling  and  fell  upon  the  brussels  and  furniture  below 
doing  great  damage.  This  proved  the  climax  of  endurance  and 
Edison  was  at  once  discharged. 

Bidding  good  bye  to  Louisville  and  with  some  regrets  for  the 
damage  done  the  bank  furniture,  Mr.  Edison  went  immediately 
to  Cincinnati  where  he  obtained  employment  as  a  "report" 
operator.  This  was  his  second  visit  to  this  point  During  his 


AND  HIS  INVENTIONS.  6x 

former  stay  he  built  an  ingenious  little  steam  engine  and  arranged 
his  first  duplex  instruments.  His  second  stay  in  Cincinnati  was 
less  popular  on  account  of  his  continued  experiments.  He 
would  get  excused  from  duty,  and  take  a  bee-line  to  the  Mech- 
anics' Library,  where  his  entire  day  and  evening  would  be  spent 
reading  the  most  ponderous  electrical  and  scientific  works.  He 
remained  in  Cincinnati  only  a  short  time,  and  returned  home  to 
Port  Huron. 

Thus  young  Edison  went  the  "grand  rounds."  a It  would  be 
gratuitously  malicious,"  sure  enough,  "to  note  so  many  queer 
mishaps,  if  they  were  thought  to  show  a  want  of  conscientious- 
ness. They  seem  to  have  been  the  result  of  an  uncontrollable 
impulse.  His  inventions  were  calling  him  with  a  sort  of  siren 
voice  and  under  the  charm  he  was  deaf  and  semi-callous  to  every- 
thing else," 


61  THOMAS  A.  EDISON 

Young  Edison  in  Boston. 

DEPARTS  FOR  THE  "  HUB"— SNOW  BOUND — His  RECEPTION— JOKE  ON 
THE  COCKROACHES — INVENTIONS — THE  GIRLS — 

Sooner  or  later  "coming  greatness"  is  apt  to  touch  at  Boston. 
Boston  is  a  great  city — the  hub  etc.  Moody  went  to  Boston. 
It  was  there  he  received  that  celebrated  letter  from  his  sister, 
charging  him  to  beware  of  pickpockets,  when,  alas,  he  hadn't  a 
nickel  in  the  world.  Of  course  young  Edison  went  to  Boston. 
He  had  a  warm  personal  friend  in  the  telegraph  office  -in  that 
city,  M.  F.  Adams,  who  was  anxions  he  should  come  and  was 
ready  to  receive  him.  An  expert  was  wanted  in  the  Boston 
office  to  work  a  heavy  New  York  wire.  Several  candidates  had 
failed  as  the  New  York  end  was  worked  by  the  "York  and  Erie" 
operators,  who,  as  a  class,  had  the  reputation  of  writing  anything 
but  the  "Morse"  alphabet.  G.  F.  Milliken,  the  manager,  offered 
the  situation  to  Edison  by  telegraph,  and  he  accepted. 

He  started  via  the  Grand  Trunk,  but  the  train  was  snowed  in 
for  two  days  near  the  bluffs  of  the  St.  Lawrence  by  a  violent 
storm.  The  passengers  nearly  perished  with  cold  and  hunger. 
All  resources  for  fuel  and  food  were  exhausted;  a  delegation 
was  sent  out  to  hunt  for  relief.  They  were  gone  so  long  another 
expedition  was  about  starting  in  search  of  them,  when  they 
returned  and  reported  a  hotel  not  far  distant  where  cigars  were 
one  cent  apiece,  and  whiskey  three  cents  a  glass,  and  board 
fifty  cents  a  day.  A  shout  of  relief  went  up  from  the  crowded 
cars,  and  they  were  soon  comfortably  housed  till  the  storm  was 
over.  Edison  finally  reached  Boston  all  right.  His  reception  at 
the  telegraph  office  by  the  young  operators  was  not  as  cordial  as 
it  might  have  been,  owing,  no  doubt,  to  jealousy.  The  table  at 
which  he  had  been  placed  was  in  the  centre  of  the  room,  located 
there,  it  is  said,  for  the  better  enjoyment  of  his  discomfiture.  He 
noticed  the  arrangement,  and  says  he  would  have  died  rathei 
than  make  a  break. 

He  arrived  in  Boston  in  1868,  and  in  the  person  of  Mr.  Milli- 
ken found  the  first  superior  officer  who  could  appreciate  hi* 


AND  HIS  INVENTIONS.  63 

character.  Mr.  Milliken  was  an  accomplished  gentleman,  a 
thorough  master  of  his  profession,  and  an  inventor  of  merit.  He 
proved  a  faithful  friend  of  Mr.  Edison  and  in  the  secret  excitement 
under  which  he  seemed  to  labor,  recognized  the  fire  of  genius. 
Edison's  stay  in  Boston  was  congenial.  There  is  a  vein  of  humor 
running  through  his  character,  and  he  played  a  practical  joke  on 
the  cockroaches  which  infested  the  office  in  great  numbers. 

He  placed  some  narrow  strips  of  tin-foil  on  the  wall  connect- 
ing them  with  the  wires  from  a  powerful  battery.  Then  he  placed 
food  on  them  in  an  attractive  manner  to  tempt  them.  When 
these  clammy  individuals  passed  from  one  foil  to  the  other  they 
completed  the  battery  connection,  and  with  a  flash  were  crema- 
ted, to  the  delight  of  the  spectators.  Edison  started  a  shop  in 
Boston,  and  gave  all  his  spare  time  to  it.  He  invented  a  dial 
instrument  for  private  line  use,  and  put  several  into  practical  op- 
eration. He  made  a  chemical  vote  recording  apparatus,  but 
failed  to  get  it  adopted  by  a  Massachusetts  Legislature.  He 
commenced  his  experiments  on  vibratory  telegraph  apparatus, 
and  made  trial  tests  between  Boston  and  Portland.  He  matured 
his  first  private  line  printer,  and  put  eight  into  practical  opera- 
tion. From  lack  of  means  to  pay  for  quotations  his  venture 
was  not  successful,  and  he  sold  out  This  patent  subsequently 
came  into  possession  of  the  Gold  and  Stock  Telegraph  Compa- 
ny, and  was  considered  to  have  a  base  or  foundation  value  upon 
which  many  subsequent  improvements  were  built. 

At  one  time  he  was  invited  to  explain  the  operation  of  the 
telegraph  to  what  he  supposed  was  a  girl's  school.  He  forgot  the 
appointment,  and  when  found  was  putting  up  a  line  on  a  house- 
top. He  went  directly  from  his  work,  and  was  much  abashed 
to  find  himself  ushered  into  the  presence  of  a  room  full  of  finely 
dressed  young  ladies.  He  was  actually  timid  in  ladies'  presence, 
but  his  subject  was  understood,  and  the  occasion  passed  pleasant- 
ly. He  was  introduced  to  a  number  of  young  ladies,  who  always 
recognized  him  on  the  street,  much  to  the  astonishment  of  his  fel- 
low-operators not  in  the  secret. 


THOMAS  A.  EDISOk 


Edison  in  New  York. 

PBNNILESS  AND  HUNGRY — THK  SUPREME  MOMENT— BRAINS— His  GREAT 
SUCCESS. 

Before  his  arrival  in  New  York,  in  1870,  Mr.  Edison,  assisted 
by  Mr.  F.  L.  Pope,  patent  adviser  of  the  Western  Union  Tele- 
graph Company,  made  a  trial  experiment  of  his  duplex  system, 
which  though  not  fully  satisfactory,  was  sufficiently  convincing 
to  engender  absolute  faith  in  its  ultimate  success.  He  then 
went  to  New  York.  The  story  of  his  arrival,  remarkable  ex- 
perience, and  the  supreme  moment  of  final  success,  in  this 
city,  is  narrated  by  one  of  his  most  intimate  friends  as  follows : 
When  Mr.  Edison  arrived  in  New  York  from  Boston,  where  he 
was  employed  as  an  operator  in  the  Western  Union  Telegraph 
office,  he  was  absolutely  penniless.  He  was  unsuccessful  in  pro 
curing  work  in  any  of  the  Tetegraph  offices,  and  there  is  no 
doubt  he  suffered  not  only  for  food,  but  for  clothes  while  he 
tramped  the  streets  on  the  look  out  for  a  job.  After  three  weeks 
of  unavailing  effort,  he  by  chance  stepped  into  the  office  of  the 
"Laws  Gold  Reporting  Telegraph  Co."  The  instrument  which 
reported  the  gold  market  was  out  of  order,  and  Mr.  Laws  the 
inventor  of  the  system  (George  Laws,  now  of  St.  Louis,  Mo.) 
was  in  despair,  when  Mr.  Edison  told  him  he  thought  he  could 
make  it  work,  and  was  given  an  opportunity.  In  a  few  moments, 
the  instrument  was  working  as  usual,  and  Mr.  Edison  had  a  situ- 
ation. This,  it  may  may  be  said,  was  the  start  towards  the  name 
which  he  has  since  earned.  From  that  time  to  the  present  date 
he  has  made  by  his  own  efforts  and  expended,  the  sum  of  nearly 
five  hundred  thousand  dollars. 

The  Indicator  Company  at  once  employed  Mr.  Edison  to  fill 
a  responsible  position  and  his  discouragements  were  at  an  end. 
He  immediately  began  the  work  of  improving  the  Indicator  and 
very  soon  invented  his  Gold  Printer.  His  next  advance  was  a 
co-partnership  with  Messrs  Pope  &  Ashley  and  the  introduction 
of  the  Pope  &  Edison  Printer.  A  private  line  system  was  put 


AND  HIS  INVENTIONS.  65 

in  active  operation,  but  was  soon  disposed  of  to  the  Gold  and 
Stock  Company. 

From  this  time  on,  T.  A.  Edison  has  been  known  and  apprecia- 
ted. His  success  was  like  the  opening  of  a  flower,  the  result  of 
long  and  stupendous  preparations,  but  blooming,  at  last,  in  a 
single  day.  For  many  years  he  has  been  retained  in  the  service 
of  the  Gold  and  Stock  Company  and  the  Western  Union  Tele- 
graph Company  at  a  large  salary,  they  having  the  first  option  to 
purchase  his  inventions  pertaining  to  telegraphy  at  prices  agreed 
upon  in  each  case.  His  inventions  pertaining  to  the  Gold  and 
Stock  Telegraph  room  replaced  the  old  apparatus,  and  that 
system  is  interwoven  with  his  inventions  and  improvements. 

Mr.  Edison's  final  triumph  is  a  matter  of  general  congratula- 
tion, not  only  because  his  patient  labors  and  long  and  dubious 
industries  merited  reward,  but  for  the  grand  field  it  opened  from 
which  the  world  has  received  some  of  its  best  inventions.  It 
has  also  its  distinctive  and  impressive  lessons.  Perseverance 
conquers.  Indomitable  will  is  power.  Ideas  are  everything. 
Deaf  to  all  derision,  determined,  though  often  disappointed, 
decided,  though  often  discharged,  Edison  went  "right  along" 
until  the  glad  hours  came. 


66  THOMAS  A.  EDISON 

Edison  in  Newark. 

Soon  after  the  intimate  relationship  was  formed  between  Mr. 
Edison  and  the  Gold  and  Stock  Company  he  removed  to  New- 
ark, New  Jersey,  where  he  established  an  immense  electrical 
manufacturing  establishment  in  which  he  employed  over  three 
hundred  men.  It  was  divided  into  three  large  shops  and  two 
laboratories.  Electrical  experiments  were  now  the  order  of  the 
day  and  Mr.  Edison,  at  this  time,  claimed  to  be  the  busiest 
man  in  America.  It  was  his  grand  opportunity.  There  was 
nothing  to  impede.  Everything  urged  him  on.  His  inventions 
multiplied,  and  soon  he  was  described  by  the  United  States  pat. 
ent  commissioner  as  "the  young  man  who  kept  the  path  to  the 
Patent  Office  hot  with  his  footsteps. "  At  one  time  he  had  forty- 
five  distinct  inventions  and  improvements  under  way. 

An  idea  of  his  determination  and  persistence  can  be  gained 
from  the  following  incident :  He  had  been  given  an  order  for 
$30,000  worth  of  improved  printers.  The  sample  instrument 
had  worked  an  experimental  circuit,  but  the  first  instruments  for 
practical  use  proved  a  failure.  In  vain  he  sought  to  remedy  the 
defect,  till  finally,  taking  four  or  five  of  his  best  men,  he  went  to 
the  top  floor  of  his  factory,  remarking  that  they  would  never 
come  down  till  the  printer  worked.  They  labored  continuously 
for  sixty  hours,  and  he  was  so  fortunate  as  to  discover  the  fault, 
and  made  the  printers  operate  perfectly  at  an  expense  of 
$5,000.  Such  severe  and  protracted  labors  are  common  with 
him.  He  says  after  going  without  sleep  more  than  the  ordinary 
hours  he  becomes  nervous,  and  the  ideas  flow  in  upon  him  with 
great  rapidity.  His  sleep  after  these  efforts  is  correspondingly 
long,  sometimes  lasting  thirty  to  thirty-six  hours.  He  knows  no 
such  division  as  day  and  night  in  his  labors,  and,  when  the  in- 
spiration is  upon  him,  pursues  the  investigation  and  experiment 
to  the  end. 

It  is  doubtful  whether  there  has  ever  lived  just  such  another 
character  as  Mr,  Edison,  whose  time  and  energies  have  been 
given  so  devotedly  and  successfully  to  the  discovery  of  practical 
inventions. 


AND  HIS  INVENTIONS.  67 

Edison's  Courtship  and  Marriage. 
Edison  was  now  master   of  the   situation.     He  was  the  king 

of  inventors,  and  far  removed  from  dangers  originating  with  su- 
perintendents, conductors,  and  such  like  dignitaries.  Yet  it 
cannot  be  said  that  he  was  "perfectly  secure."  In  another  direc- 
tion, entirely  different,  new  influences  were  silently  operating 
that  soon  demonstrated  the  young  inventor  to  be  not  wholly 
invulnerable.  It  was  trivial  at  first,  but  gradually  became  a 
serious  matter.  He  was  evidently  within  the  influence  of  a  pe- 
culiar magnetic  battery,  which  he  could  not  fully  control.  To 
get  beyond  the  magic  power  was  impossible.  The  sequel  to  all 
this  was  his  marriage  in  1873  to  Miss  Mary  Still  well,  of  New- 
ark, N.  J.  The  medallion  on  the  new  silver  dollar  is  pronounced 
an  excellent  profile  likeness  of  Mrs.  Edison.  The  story  of  his 
love  and  marriage  is  briefly  told  as  follows: 

When  he  was  experimenting,  some  years  ago,  with  the  little 
automatic  telegraph  system,  he  perfected  a  contrivance  for  pro- 
ducing perforations  in  paper  by  means  of  a  key-board.  Among 
the  young  women  whom  he  employed  to  manipulate  these  ma- 
chines, with  a  view  to  testing  their  capacity  for  speed,  was  a 
rather  demure  young  person  who  attended  to  her  work  and 
never  raised  her  eyes  to  the  incipient  genius.  One  day  Edison 
stood  observing  her  as  she  drove  down  one  key  after  another 
with  her  plump  fingers,  until,  growing  nervous  under  his  prolonged 
stare,  she  dropped  her  hands  idly  in  her  lap,  and  looked  up 
helplessly  into  his  face.  A  genial  smile  overspread  Edison's 
face,  and  he  presently  inquired  rather  abruptly: 

"What  do  you  think  of  me,  little  girl?     Do  you  like  me?" 

"Why,  Mr.  Edison,  you  frighten  me.     I — that  is — I " 

"Don't  be  in  any  hurry  about  telling  me.  It  doesn't  matter 
much,  unless  you  would  like  to  marry  me. " 

The  young  woman  was  disposed  to  laugh,  but  Edison  went  on : 
"Oh,   I  mean  it.     Don  t  be  in  a  rush,  though.     Think  it  over; 
talk  to  your  mother  about  it,  and  let  me  know  soon  as  conven- 
ient— Tuesday  say.     How  will  Tuesday  suit  you,  next  week 
Tuesday,  I  mean?" 


68  THOMAS  A.  EDISON 

Edison's  shop  was  at  Newark  in  those  days,  and  one  night  a 
friend  of  his,  employed  in  the  main  office  of  the  Western  Union 
Telegraph  Company,  hi  New  York,  returning  home  by  the  last 
train,  saw  a  light  in  Edison's  private  laboratory,  and  climbed  the 
stairs  to  find  his  friend  in  one  of  his  characteristic  stupors, 
half  awake  and  half  dozing  over  some  intricate  point  in  electri- 
cal science  which  was  baffling  him. 

"Halloo  Tom?"  cried  the  visitor  cheerily,  "what  are  you  doing 
here  this  late?  Aren't  you  going  home?" 

"What  time  is  it?"  inquired  Edison,  sleepily  rubbing  his  eyes 
and  stretching  like  a  lion  suddenly  aroused. 

"Midnight  easy  enough.     Come  along." 

"Is  that  so?"  returned  Edison  in  a  dreamy  sort  of  a  way. 
"By  George.  I  must  go  home,  then.  I  was  married  to-day." 

Marriage  was  an  old  story  with  him — he  had  been  wedded  to 
electrical  hobbies  for  years.  But,  in  spite  of  his  seeming  indif- 
ference on  "the  most  eventful  day"  in  his  life,  he  makes  a  good 
husband,  and  the  pretty  little  woman  of  the  perforating  machine 
smilingly  rules  domestic  destinies  at  Menlo  Park,  and  proudly 
looks  across  the  fields  where  chimneys  rise  and  her  husband  still 
works  on  the  problems  that  made  him  a  truant  on  his  wedding 
day.  A  swarm  of  children  pluck  her  gown  to  share  then*  mother's 
smile,  and  lay  in  wait  to  climb  into  their  father's  lap  and  muss 
his  hair  with  as  great  a  relish  as  if  he  were  not  the  greatest 
genius  of  his  time.  The  pet  names  of  two  of  these  little  ones  are 
"Dot"  and  "Dash, " — after  the  characters  in  the  Morse  alphabet — 
and  a  third,  only  three  months  old,  is  called  William  Leslie. 
Dot's  real  name  is  Mary  Estelle,  and  Dash's,  Thomas  Alva  Edi- 
son, Jr. 


AND  HIS  INVENTIONS.  69 

In  Menlo  Park. 

In  his  arduous  labors  at  Newark,  Mr.  Edison  was  subject  to 
constant  annoyance  arising  from  the  great  tax  upon  his  powers, 
curiosity  seekers,  etc.,  which  finally  causd  him  to  dispose  of  his 
expensive  machinery  and  seek  a  more  retired  spot,  where  he 
could  quietly  put  into  practical  shape,  his  grand  ideas  connected 
with  various  mechanisms.  He  accordingly  removed  with  his 
family,  in  1876,  to  Menlo  Park,  a  retired  place,  on  the  line  of 
the  New  York  &  Philadelphia  railroad,  two  miles  north  of 
Metuchin  and  twenty-four  miles  from  New  York.  At  this  point 
Mr.  Edison  then  erected  and  fitted  up  the  most  extensive  labora- 
tory in  the  world.  Mr.  Reid  in  his  Memorial  Volume  pronoun- 
ces it  "one  of  the  amplest  laboratories  and  the  finest  array  of 
assisting  machinery  to  be  found  in  connection  with  scientific 
inquiry. " 

Mr.  Edison  has  very  recently  enlarged  his  facilities  for  his  line 
of  business  by  completing  a  workshop  one  hundred  by  thirty-five 
feet — about  the  same  size  of  the  old  one — which  is  fitted 
up  in  the  best  possible  manner  with  appropriate  machinery.  The 
engine  in  the  new  building  is  an  eighty  horse  power,  built  by 
Charles  Browne  and  Co.,  and  said  to  be  one  of  the  finest  and 
best  made  engines  in  the  United  States.  The  boiler  is  of  the 
latest  pattern,  sectional,  while  the  lathes,  punches,  drills,  planers, 
milling  machines,  etc.,  are  from  the  best  makers. 

The  experimental  apparatus  is  the  very  finest  and  has  been 
obtained  by  Mr.  Edison  at  an  expense  of  $100,000,00.  The 
facilities  for  " getting  out  an  invention"  are  far  superior  to  any 
other  laboratory  in  the  world.  It  is  not  an  uncommon  thing  for 
Mr.  Edison  to  make  an  invention  in  the  morning,  and  before 
night  receive  the  working  model  for  the  same,  from  the  hands  of 
his  chief  assistant.  It  is  in  this  stupendous  and  splendid  labora- 
tory that  the  great  professional  inventor  is  jjnow  at  work,  day 
and  night,  astonishing  the  civilized  world  by  the  character  and 
number  of  his  discoveries.  The  interior  of  this  wonderful  es- 


fo  THOMAS  A.  JEJDIS02V 

tablishment  is  described  in  detail  in  an  earlier  chapter  of  this 
volume. 

In  every  well  regulated  institution  of  this  character  there  are 
always  a  number  of  faithful  co-workers  who  merit  the  highest 
commendations.  Mr.  Charles  Batchelor,  who  is  Mr.  Edison's 
chief  assistant,  has  been  with  him  for  the  last  nine  years  and 
has  helped  him  to  perfect  all  his  inventions.  He  is  a  gentleman  of 
superior  ability  and  integrity.  Under  his  supervision,  Mr.  Edison 
keeps  eleven  of  the  most  skillful  machinists  and  instrument 
makers  to  be  found  in  the  country — some  of  whom  have  been 
employed  for  years — and  a  corps  of  laboratory  assistants. 

Professor  Mclntyre,  an  accomplished  scholar  and  noted 
chemist,  with  two  assistants  are  kept  constantly  engaged  on 
original  research  under  Mr.  Edison's  own  special  direction.  The 
inventor's  extensive  correspondence  is  attended  to  by  Mr.  L.  S. 
Griffin,  his  private  secretary,  a  life  long  friend  and  former  tele- 
graph manager.  He  also  attends  to  financial  and  confidential 
matters.  William  Carman  is  book-keeper,  and  Mr.  John  Kreuzi 
master  machinist.  To  all  of  these  faithful  co-laborers  Mr. 
Edison  pays  stated  wages  in  the  usual  manner,  except  Mr. 
Batchelor,  to  whom  he  gives  an  interest  in  the  inventions  when 
perfected. 

The  analysis  of  labor  is  so  perfect  that  the  whole  establishment 
moves  along  like  clock-work.  Each  workman  is  interested  in 
the  success  of  every  important  invention  and,  it  is  said,  does  not 
care  so  much  for  the  exact  hours  of  his  labors,  as  is  generally 
done  in  extensive  manufactories.  Edison  is  seen  frequently 
among  his  men,  genial  and  jovial,  but  moving  through  all  as  the 
grand  master  spirit,  which  he  is. 


AND  HIS  INV-ENTIONS.  71 

Edison's  Principal  Inventions. 

In  his  new  and  extensive  factory  at  Llewellyn  Pane, 
Orange  County,  N.  J.,  Mr.  Edison,  with  a  large  corps  of  com- 
petent assistants,  is  constantly  busy  in  "  turning  out  inven- 
tions," as  was  done  in  Newark  and  Menlo  Park.  Among 
the  principal  inventions  in  the  catalogue  are  the  following: 

The   new   and   perfected  Phonograph,  including   the  Re- 
ceiver and  Reproducer. 
New  Edison  Dynamo. 
Incandescent  House  Lamp. 
Incandescent  Municipal  Lamp. 
Pyro-Magnetic  Dynamo. 
Ground  Detector. 
Junction  Box  and  Safety  Catch. 
Train  Telegraphic  Apparatus. 
Mimeograph. 
Improved  Phonoplex. 
Sea  Telephone. 
Button  Repeater. 
Gold  and  Stock  Printer. 
Private  Line  Printer. 
Automatic  Telegraph. 
Etheric  Force  (a  new  discovery.) 
Electric  Pen  and  Press. 
Duplex  Telegraph. 
Domestic  Telegraph  System. 
Electro-Holograph  (a  new  discovery.) 
The  Acoustic  Telegraph. 
The  Carbon  Speaking  Telephone. 
The  Pressure  Relay  (a  new  discovery.) 
The  Msgophone. 
The  Aerophone. 
The  Tasimeter,  or  "Minute  Heat  Measure." 


72  THOMAS  A.  EDISON 

Harmonic  Engine. 

Multiplying  Copying  Ink. 

Vocal  Engine. 

The  Sonorous  Voltameter. 

Subdivision  of  the  Electric  Light. 

Mining' Apparatus  for  Separating  Ores,  Etc.,  Etc. 

At  present  he  is  improving  the  Phonograph;  Electric 
Light;  process  for  separating  gold  and  silver  from  ores;  the 
Telephone,  etc.,  etc. 

A  single  invention  is  sometimes  covered  by  from  fifteen 
to  twenty  or  more  patents,  the  patent  laws  not  allowing  one 
patent  to  cover  all  the  essential  points.  Edison's  stock  tele- 
graph instrument  is  covered  by  forty  patents;  his  quadruplex 
telegraph  by  eleven;  and  his  automatic  system  of  telegraphy 
by  forty-six. 

Mr.  Edison's  electric  light  system  alone  is  operated  under 
about  one  thousand  patents! 

Mr.  Edison  patents  his  inventions  in  Europe  as  well  as  in 
this  country.  The  following  story  from  him  illustrates  how 
quickly  it  may  be  done: 

"I  made  a  discovery  at  four  o'clock  in  the  afternoon.  I  got 
a  wire  from  here  (Menlo  Park)  to  Plainfield,  where  my 
solicitor  lives,  and  brought  him  into  the  telegraph  office  at 
that  place.  I  wired  him  my  discovery.  He  drew  up  the 
specifications  on  the  spot,  and  about  nine  o'clock  that  night 
cabled  an  application  for  a  patent  to  London.  Before  I  was 
out  of  bed  the  next  morning  I  received  word  from  London 
that  my  application  had  been  filed  in  the  English  patent 
office.  The  application  was  filed  at  noon,  and  I  received  my 
information  about  seven  in  the  morning,  five  hours  before 
the  filing.  The  difference  between  London  and  New  York 
time  explains  the  thing." 


AND  HIS  INVENTIONS.  73 

The  Quadruplex. 

A  WONDERFUL  INVENTION— FOUR  DIFFERENT  MESSAGES  SENT  AT  SAMB 

TIME  OVER  A  SINGLE  WIRE— How  IT 

Is  DONB. 

If  we  were  writing  a  volume  on  science,  under  this  caption  we 
should  give  a  page  to  the  wonders  of  electricity.  But  this  is  not 
our  aim^and  therefore  the  reader  must  simply  accept  it  as  a  won- 
derful fact  that  by  Edison's  quadruplex  system,  four  separate  and 
distinct  messages,  two  in  each  direction,  may  pass  simultaneously 
over  a  single  wire.  Mr.  Reid  well  remarks  in  his  "Memorial 
Volume,"  that  "the  chief  product  of  Mr.  Edison's  genius  has 
been  the  quadruplex  system  of  telegraphy,  by  which  already 
the  equivalent  of  fifty  thousand  miles  of  wire  have  been. added 
to  the  capacity  of  the  lines  of  the  Western  Union  Telegraph 
Company. ''  If  Mr.  Edison  had  perfected  no  other  mechanism, 
this  alone  would  rank  him  among  the  greatest  of  public  bene- 
factors. 

It  was  during  the  summer  of  1874,  at  Newark,  N.  J.,  while 
engaged  in  conjunction  with  Mr.  Prescott,  of  New  York,  in  ex- 
perimenting upon  Stearns'  duplex  apparatus  with  a  view  of  in- 
troducing certain  modifications  that  Mr.  Edison  discovered  the 
basis  of  the  quadruplex  system. 

The  distinguishing  feature  of  this  method  of  telegraphy  con- 
sists in  combining  at  two  terminal  stations,  two  distinct  and  un- 
like methods  of  single  transmission,  in  such  a  manner  that  they 
may  be  carried  on  independently  upon  the  same  wire,  and  at  the 
same  time,  without  interfering  with  each  other.  One  of  these 
methods  of  single  transmission  is  known  as  the  double  current 
system,  and  the  other  is  the  single  current  or  open  circuit  system. 

In  the  double  current  system  the  battery  remains  constantly 
in  connection  with  the  line  at  the  sending  stations,  its  polarity 
being  completely  reversed  at  the  beginning,  and  at  the  end  of 
every  signal,  without  breaking  the  circuit.  The  receiving  relay 
is  provided  with  a  polarized  or  permanently  magnetic  armature, 
but  has  no  adjusting  spring,  and  its  action  depends  solely  upon 


74 


THOMAS  A.  EDISON 


the  reversal  or  polarity  upon  the  line,  without  reference  to  the 
strength  of  the  current 

In  the  single  current  system,  the  transmission  is  effected  by 
increasing  and  decreasing  the  current,  while  the  relay  may  have 
a  neutral  soft  iron  armature,  provided  with  a  retracting  spring. 
A  more  desirable  form,  however,  for  long  circuits,  is  that  of 
the  polarized  relay,  especially  adopted  to  prevent  interferences 
from  the  reversals  sent  into  the  line  to  operate  the  double 
current  system.  The  action,  therefore  in  this  system,  depends 
solely  upon  the  strength  of  the  current,  its  polarity  being  a 
matter  of  indifference. 

By  making  use  of  these  two  methods,  viz.,  polarity  and  strength, 
combined  with  the  duplex  principle  of  simultaneous  transmission 
in  opposite  directions,  four  sets  of  instruments  may  be  operated 
at  the  same  time,  on  the  same  wire. 

Z.//V& 


The  Ouadruplex.    D  T,  Double  Transmitter;  S  T,  Second  or  Single  Transmitter;  P,  Polar- 
ised Relay;  C  R,  Common  Relay;  C,  Condenser;  G,  Ground,   x 


, 
and  3  Batteries. 


AND  HIS  INVENTIONS. 


Phonograph  in  Operation. 

The  Phonograph. 

THB  EDISON  AND   FABER    "TALKING  MACHINES" — PHONOGRAPH  FULLY 

EXPLAINED — ITS  FIDELITY  IN  RE-PRODUCING  SOUND — 

WHAT  WE  MAY  EXPECT  FROM  IT. 

No  invention  in  the  world's  history  has  engendered  more  curi- 
osity than  the  Phonograph.  And  yet  of  all,  it  may  be  considered 
among  the  most  simple  as  well  as  singular.  Efforts  were  made 
long  ago  to  produce  a  "  talk  ing  machine, "  but  they  were  attended 
with  no  great  degree  of  success.  The  organs  of  speech  were 
well  imitated  by  excellent  mechanisms  and  vibrations  were  pro- 
duced which  gave  out  a  sound  similar  to  the  human  voice,  but  it 
was  after  all  only  a  species  of  the  pipe  organ,  and  too  compli- 
cated and  expensive  to  be  of  any  practical  value.  By  an  entirely 
different  principle,  in  which  the  vibrations  of  the  voice  are  com- 
municated at  once  upon  a  mctalic  surface,  becoming  thereby 


76  THOMAS  A.  EDISON 

fixed,  as  so  many  indentations  representing  exactly  the  words  spo- 
ken, Mr.  Edison  has  developed  a  simple  mechanism  that  repro- 
duces with  wonderful  exactness  the  human  voice  in  all  its  possible 
variations. 

Professor  Faber,  in  developing  his  machine,  worked  at  the 
source  of  articulate  sounds,  and  built  up  an  artificial  organ  of 
speech,  whose  parts,  as  nearly  as  possible,  perform  the  same 
functions  as  corresponding  organs  in  our  vocal  apparatus.  A  vi- 
brating ivory  reed,  of  variable  pitch,  forms  its  vocal  chords. 
There  is  an  oral  cavity  whose  size  and  shape  can  be  rapidly 
changed  by  depressing  the  keys  on  a  key-board.  A  rubber 
tongue  and  lips  make  the  consonants;  a  little  windmill,  turning 
in  its  throat,  rolls  the  letter  r,  and  a  tube  is  attached  to  its  nose 
when  it.  speaks  French.  This  is  the  anatomy  of  Faber's  won- 
derful piece  of  mechanism. 

Faber  attacked  the  problem  on  its  physiological  side.  Quite 
differently  works  Mr.  Edison :  he  attacks  the  problem,  not  at 
the  source  of  origin  of  the  vibrations  which  make  articulate 
speech:  but  considering  these  vibrations  as  already  made,  it 
matters  not  how,  he  makes  these  vibrations  impress  themselves 
on  a  sheet  of  metallic  foil,  and  then  reproduces  from  these  im- 
pressions the  sonorous  vibrations  which  made  them. 

Faber  solved  the  problem  by  reproducing  the  mechanical 
causes  of  the  vibrations  making  voice  and  speech;  Edison 
solved  it  by  taking  the  mechanical  effects  of  these  vibrations. 
Faber  reproduced  the  movements  of  our  vocal  organs;  Edison 
reproduced  the  motions  which  the  drum-skin  of  the  ear  has 
when  this  organ  is  acted  on  by  the  vibrations  caused  by  the 
movements  of  the  vocal  organs. 

The  simplicity  of  Mr.  Edison's  mechanism  and  its  fidelity  in 
reproducing  sound,  enthrone  the  phonograph  as  king  in  the  realm 
of  wonderful  inventions.  Geo.  B.  Prescott,  a  friend  of  Mr.  Edi- 
son, and  electrician  of  the  Western  Union  Telegraph  Company 
at  New  York  says  that  "certainly,  within  a  dozen  years,  some 
of  the  great  singers  will  be  induced  to  sing  into  the  ear  of  the 
phonograph,  and  the  stereotyped  cylinders  thence  obtained  will 


AND  HIS  INVENTIONS.  77 

be  put  into  the  hand  organs  of  the  streets,  and  we  shall  hear  the 
actual  voice  of  Christine  Nilsson  or  Miss  Gary  ground  out  at 
every  corner.  In  public  exhibitions,  also,  we  shall  have  re- 
productions of  the  sounds  of  nature,  and  of  noises  familiar  and 
unfamiliar.  Nothing  will  be  easier  than  to  catch  the  sounds  of 
the  waves  on  the  beach,  the  roar  of  Niagara,  the  discords  of 
the  street,  the  voice  of  animals,  the  puffing  and  rush  of  the  rail- 
road, the  rolling  thunder,  or  even  the  tumult  of  a  battle. " 

"In  its  simplest  form,  the  speaking  phonograph"  says  Mr. 
Prescott,  "consists  of  a  mounted  diaphragm,  so  arranged  as  to 
operate  a  small  steel  stylus  or  needle  point,  placed  just  below 
and  opposite  its  center,  and  a  brass  cylinder,  six  or  more 
inches  long  by  three  or  four  in  diameter,  which  is  mounted 
on  a  horizontal  axis  extending  each  way  beyond  its  ends  for  a 
distance  about  equal  to  its  own  length.  A  spiral  groove  is  cut 
in  the  circumference  of  the  cylinder,  from  one  end  to  the  other, 
each  spiral  of  the  groove  being  separated  from  its  neighbor  by 
about  one-tenth  of  an  inch.  The  shaft  or  axis  is  also  cut  by  a 
screw  thread  corresponding  to  the  spiral  groove  of  the  cylinder, 
and  works  in  screw  bearings,  consequently  when  the  cylinder  is 
caused  to  revolve,  by  means  of  a  crank  that  is  fitted  to  the  axis 
for  this  purpose,  it  receives  a  forward  or  backward  movement  of 
about  one-tenth  of  an  inch  for  every  turn  of  the  same,  the  di- 
rection, of  course,  depending  upon  the  way  the  crank  is  turned. 
The  diaphragm  is  supported  by  an  upright  casting  capable  of  ad 
justment,  and  so  arranged  that  it  may  be  removed  altogethei 
when  necessary.  When  in  use,  however,  it  is  clamped  in  a  fixec 
position  above  or  in  front  of  the  cylinder,  thus  bringing  the 
stylus  always  opposite  the  groove  as  the  cylinder  is  turned.  .A 
small,  flat  spring  attached  to  the  casting  extends  underneath  the 
diaphragm  as  far  as  its  center  and  carries  the  stylus,  and  between 
the  diaphragm  and  spring  a  small  piece  of  india  rubber  is  placed 
to  modify  the  action,  it  having  been  found  that  better  results  art 
obtained  by  this  means  than  when  the  stylus  is  rigidly  attached 
to  the  diaphragm  itself. 

The  action  of  the  apparatus  will  now  be  readily  understood 


f8  THOMAS  A.  EDISON 

from  what  follows.  The  cylinder  is  first  very  smoothly  covered 
with  tin-foil,  and  the  diaphragm  securely  fastened  in  place  by 
clamping  its  support  to  the  base  of  the  instrument.  When  this 
has  been  properly  done,  the  stylus  should  lightly  press  against 
that  part  of  the  foil  over  the  groove.  The  crank  is  now  turned, 
while,  at  the  same  time,  some  one  speaks  into  the  mouth-piece 
of  the  instrument,  which  will  cause  the  diaphragm  to  vibrate, 
and  as  the  vibrations  of  the  latter  correspond  with  the  move- 
ments of  the  air  producing  them,  the  soft  and  yielding  foil  will 


The  Phonograph. 


become  marked  along  the  line  of  the  groove  by  a  series  of  in- 
dentations of  different  depths,  varying  with  the  amplitude  of  the 
vibrations  of  the  diaphragm;  or,  in  other  words,  with  the  in- 
flections or  modulations  of  the  speaker's  voice.  These  inflec- 
tions may  therefore  be  looked  upon  as  a  sort  of  visible  speech, 
which,  in  fact,  they  really  are.  If  now  the  diaphragm  is  re- 
moved, by  loosening  the  clamp,  and  the  cylinder  then  turned 
back  to  the  starting  point,  we  have  only  to  replace  the  dia- 
phragm and  turn  in  the  same  direction  as  at  first,  to  hear  re- 
peated all  that  has  been  spoken  into  the  mouth-piece  of  the 
apparatus;  the  stylus,  by  this  means,  being  caused  to  traverse 
its  former  path,  and  consequently,  rising  and  falling  with  the  de- 
pressions in  the  foil,  its  motion  is  communicated  to  the  dia- 
phragm, and  thence  through  the  intervening  air  to  the  ear,  where 
the  sensation  of  sound  is  produced. 


AND  HIS  INVENTIONS.  79 

As  the  faithful  reproduction  of  a  sound  is  in  reality  nothing 
more  than  a  reproduction  of  similar  aucoustic  vibrations  in  a 
given  time,  it  at  once  becomes  evident  that  the  cylinder  should 
be  made  to  revolve  with  absolute  uniformity  at  all  times,  other- 
wise a  difference  more  or  less  marked  between  the  original  sound 
-nd  the  reproduction  will  become  manifest.  To  secure  this  uni- 
formity of  motion,  and  produce  a  practically  working  machine 
for  recording  speeches,  vocal  and  instrumental  music,  and  per- 
fectly reproducing  the  same,  the  inventor  has  devised  an  appa- 
ratus in  which  a  plate  replaces  the  cylinder.  This  plate  which  is 
ten  inches  in  diameter,  has  a  volute  spiral  groove  cut  in  its  sur- 
face on  both  sides  from  its  center  to  within  one  inch  of  its  outer 
edge;  an  arm  guided  by  the  spiral  upon  the  under  side  of  the 
plate  carries  a  diaphragm  and  mouthpiece  at  its  extreme  end. 
If  the  arm  be  placed  near  the  center  of  the  plate  and  the  latter 
rotated,  the  motion  will  cause  the  arm  to  follow  the  spiral  out- 
ward to  the  edge.  A  spring  and  train  of  wheel-work  regulated 
by  a  friction  governor  serves  to  give  uniform  motion  to  the  plate. 
The  sheet  upon  which  the  record  is  made  is  of  tin-foil.  This 
is  fastened  to  a'  paper  frame,  made  by  cutting  a  nine-inch  disk 
from  a  square  piece  of  paper  of  the  same  dimensions  as  the 
plate.  Four  pins  upon  the  plate  pass  through  corresponding 
eyelet-holes  punched  in  the  four  corners  of  the  paper,  when  the 
latter  is  laid  upon  it,  and  thus  secure  accurate  registration  while 
a  clamping-frame  hinged  to  the  plate,  fastens  the  foil  and  its 
paper  frame  securely  to  the  latter.  The  mechanism  is  so  ar- 
ranged that  the  plate  may  be  started  and  stopped  instantly  or  its 
motion  reversed  at  will,  thus  giving  the  greatest  convenience  to 
both  speaker  and  copyist. 

The  sheet  of  tin-foil  or  other  plastic  material  receiving  the 
impressions  of  sound,  may  be  stereotyped  or  electrotyped  so  as 
to  be  multiplied  and  made  durable;  or  the  cylinder  may  be  made 
of  material  plastic  when  used,  and  hardening  afterward.  Thin 
sheets  of  papier  mache,  or  of  various  substances  which  soften  by 
heat  would  be  of  this  character.  Having  provided  thus  for  the 
durability  of  the  phonograph  plate,  it  will  be  very  easy  to  make 


8o  THOMAS  A.  EDISON 

it  separable  from  the  cylinder  producing  it,  and  attaching  it  to  a 
corresponding  cylinder  anywhere  and  at  any  time.  There  will 
doubtless  be  a  standard  of  diameter  and  pitch  of  screw  for  pho- 
nograph cylinders.  Friends  at  a  distance  will  then  send  to  each 
other  phonograph  letters,  which  will  talk  at  any  time  in  the 
friend's  voice  when  put  upon  the  instrument.  How  startling 
also  it  will  be  to  reproduce  and  hear  at  pleasure  the  voice  of  the 
dead !  All  of  these  things  are  to  be  common,  every-day  expe- 
riences within  a  few  years. 


Possibilities  of  the  Phonograph. 

A   SHORT  HAND  REPORTER— ELOCUTIONIST— OPERA  SINGER— TEACHER 
OF  LANGUAGES — ITS  MEDICAL  POSSIBILITIES. 

In  speaking  of  the  various  purposes  for  which  the  phonograph 
may  be  utilized,  Mr.  Edison  says : 

u First. — For  dictating  it  will  take  the  place  of  short-hand  re- 
porters, as  thus :  A  man  who  has  many  letters  to  write  will  talk 
them  to  the  phonograph,  and  send  the  sheets  directly  to  his  cor- 
respondents, who  will  lay  them  on  the  phonograph  and  hear  what 
they  have  to  say.  Such  letters  as  go  to  people  who  have  no 
phonographs  will  be  copied  from  the  machine  by  the  office  boy. 

u  Second. — For  reading.  A  first-class  elocutionist  will  read 
one  of  Dickens'  novels  into  the  phonograph.  It  can  all  be 
printed  on  a  sheet  ten  inches  square,  and  these  can  be  multi- 
plied by  the  million  copies  by  a  cheap  process  of  electrotyping. 
These  sheets  will  be  sold  for,  say,  twenty-five  cents.  A  man  is 
tired,  and  his  wife's  eyes  are  failing,  and  so  they  sit  around  and 
hear  the  phonograph  read  from  this  sheet  the  whole  novel  with  all 
the  expression  of  a  first-class  reader.  See?  A  company  for 
printing  these  is  already  organized  in  New  York. 

"  Third. — It  will  sing  in  the  very  voice  of  Patti  and  Kellogg, 
so  that  every  family  can  have  an  opera  any  evening. 

"Fourth. — It  may  be  used  as  a  musical  composer.  When 
singing  some  favorite  airs  backward  it  hits  some  lovely  airs,  and 


AND  HIS  INVENTIONS.  81 

I  believe  a  musician  could  get  one  popular  melody  every  day 
by  experimenting  in  that  way. 

u  Fifth. — It  may  be  used  to  read  to  inmates  of  blind  asylums, 
or  to  the  ignorant,  who  have  never  learned  to  read. 

u  Sixth. — It  may  be  used  to  teach  languages,  and  I  have  al- 
ready sold  the  right  to  use  it  to  teach  children  the  alphabet. 
Suppose  Stanley  had  had  one  and  thus  obtained  for  the  world 
all  the  dialects  of  Central  Africa! 

"Seventh. — It  will  be  used  to  make  toys  talk.  A  company 
has  already  organized  to  make  speaking  dolls.  They  will  speak 
in  a  little  girl's  voice  and  will  never  lose  the  gift  any  more  than 
a  little  girl. 

u  Eighth. — It  will  be  used  by  actors  to  learn  the  right  readings 
of  passages.  In  fact,  its  utility  will  be  endless. " 

A  leading  medical  journal  asserts  that  the  phonograph  opens 
up  a  vista  of  medical  possibilities  delightful  to  contemplate: 
Who  can  fail  to  make  the  nice  distinctions  between  every  form 
of  bronchial  and  pulmonary  rale,  percussion,  succussion,  and 
friction  sounds,  surgical  crepitus,  faetal  and  placental  murmurs, 
and  arterial  and  aneurismal  bruit,. when  each  can  be  produced  at 
will,  amplified  to  any  desired  extent,  in  the  study,  the  ampi- 
theatre,  the  office,  and  the  hospital  ?  The  lecturer  of  the  future 
will  teach  more  effectively  with  this  instrument  than  by  the 
mouth.  The  phonograph  will  record  the  frequency  and  charc- 
teristics  of  respiratory  and  muscular  movements,  decide  as  to 
the  age  and  sex  of  the  faetus  in  utero,  and  differentiate  pneu- 
monia from  phthisis.  It  will  reproduce  the  sob  of  hysteria,  the 
sigh  of  melancholia,  the  singultus  of  collapse,  the  cry  of  the 
puerperal  women  in  the  different  stages  of  labor.  It  will  inter- 
pret for  the  speechless  infant,  the  moans  and  cries  of  tubercular 
meningitis,  ear-ache,  and  intestinal  colic.  It  will  furnish  the 
ring  of  whooping-cough  and  the  hack  of  the  consumptive.  It 
will  be  an  expert  in  insanity,  distinguishing  between  the  laugh 
of  the  maniac  and  the  drivel  of  the  idiot.  It  will  classify  dys- 
phasic  derangements,  such  as  ataxic,  amnesic,  paraphasic  and 
phataphasic  aphasia. 
6 


82  THOMAS  A.  EDISON 

It  will  recount,  in  the  voice  and  words  of  the  patient,  the  ago- 
nies of  neuralgia  and  renal  calculus,  and  the  horrors  of  delirium 
tremens.  It  will  give  the  burden  of  the  story  of  the  old  lady 
who  recounts  all  the  ills  of  her  ancestors  before  proceeding  to 
the  era  of  her  own.  More  than  this,  it  will  accomplish  this  feat 
in  the  ante-room,  while  the  physician  is  supposed  to  be  busying 
himself  with  his  last  patient. 

Last,  but  not  least,  it  will  simultaneously  furnish  to  the  med- 
ical philosopher  the  grateful  praises  and  promises  of  him  who  is 
convalescent  from  dangerous  illness,  together  with  the  chilling 
accents,  in  which,  later,  the  doctor  is  told  that  he  must  wait  for 
his  remuneration  till  the  butcher  and  the  baker  have  been  paid. 


The  Phonograph's  Arrival  "Out  West." 

IT    VISITS    CHICAGO— Is  INTERVIEWED   BY   A   REPORTER— A   MODERN 
MIRACLE— How  IT  TALKED— WHAT  IT  HAD  To  SAY. 

While  the  phonograph  is  a  great  traveler,  and  has  already  vis- 
ited most  of  the  civilized  world,  conversing  with  kings  and 
queens,  and  attending  great  expositions,  etc.,  yet  its  trip  out 
West  will  always  remain  among  the  most  remarkable  of  its  ear- 
liest adventures.  Wherever  exhibited,  it  proved  an  object  of  the 
greatest  interest.  Its  arrival  in  Chicago  was  heralded  as  the 
"Modern  Miracle,"  and  the  whole  occasion  is  described  by  an 
intelligent  spectator  as  follows: 

The  phonograph  has  come.  It  was  interviewed  this  morning. 
The  creature  was  found  screwed  up  in  a  box  and  manifested  no 
unruly  tendencies.  It  does  not  stand  on  its  hind  legs  at  the 
sight  of  visitors,  and  is  apparently  perfectly  safe  for  children  to 
approach  and  even  handle,  but  there  is  no  denying  that  it  does 
perform  some  most  remarkable  capers.  At  these  the  Western  pub- 
lic will  soon  be  accorded  the  privilege  of  wondering  with  open- 
mouthed  amazement.  The  instrument,  or  instruments — for 
there  are  three  of  them — are  in  the  possession  of  Mr.  Geo.  H. 
Bliss,  General  Manager  of  the  Western  Electric  Manufacturing 


AND  HIS  INVENTIONS.  83 

Company,  a  friend  of  Edison,  the  inventor,  who  has  been  awarded 
the  privilege  of  exhibiting  the  modern  miracle  in  Illinois.  They 
arrived  yesterday  afternoon,  and  were  enclosed  in  an  apartment 
of  the  Methodist  Church  Block,  from  which  it  was  deemed  prob- 
able that  they  would  be  unable  to  effect  an  escape.  They  are  the 
very  first  of  their  genus  that  have  ever  been  brought  to  this  part 
of  the  country,  and,  of  course,  their  keeper  is  very  careful  of 
them. 

This  morning,  when  the  cover  was  carefully  removed  from  the 
box,  the  reporter  drew  near  and  cautiously  looked  in,  but  imme- 
diately started  back,  expecting  the  thing  to  jump. 
"Don't  be  afraid,"  said  Mr.  Bliss;  "it  won't  bite." 
Whereupon  Mr.  Chase,  a  friend  of  Mr.  Bliss,  and  the  reporter 
were  sufficiently  re-assured  to  allow  Mr.  Bliss  to  remove  the  ma- 
chine from  its  lair,  and  place  it  on  the  table.  An  inspection  of 
it,  conducted  with  increasing  boldness,  as  it  was  observed  to  be 
entirely  harmless,  served  to  show  that  it  consisted  of  an  iron 
cylinder,  about  five  inches  in  diameter  and  six  in  length,  into 
which  was  cut  an  ordinary  screw-thread,  running  from  end  to 
end.  This  cylinder  was  swung  on  an  axle,  projecting  at  each 
end  about  the  length  of  the  cylinder,  and  also  circled  by  a  screw 
thread  corresponding  to  that  on  the  cylinder.  To  the  end  of 
the  axle  was  attached  a  small  crank,  by  means  of  which  the  cyl- 
inder could  be  revolved,  so  as  to  work  end-for-end  on  the  axle- 
supports.  The  mouth-piece  is  a  small  round  disk  of  thin  tin, 
having  a  concave  surface  calculated  to  catch  the  sound,  sup- 
ported by  a  moveable  rest,  so  that  it  can  be  swung  close  to  or 
away  from  the  cylinder.  Fixed  to  the  under  side  of  this  mouth- 
piece, by  means  of  cement,  is  a  minute  chisel-shaped  needle 
which,  when  the  rest  is  brought  close  to  the  cylinder,  would  im- 
pinge into  the  screw-thread  thereon.  This  was  the  simple  con- 
trivance. Now  in  order  to  make  it  speak,  all  that  was  necessary 
was  to  wind  the  cylinder  with  a  piece  of  smooth  tin  foil,  fasten- 
ing the  ends  of  the  sheet  with  cement  The  crank  is  then 
turned  so  that  the  cylinder  is  run  clear  to  one  end  of  the  frame, 
and  the  mouth-piece  is  brought  close  to  the  cylinder,  the  little 


84  THOMAS  A.  EDISON 

needle  being  very  nicely  adjusted  against  the  tin  foil.  Then,  as 
the  words  are  spoken  into  the  mouth-piece,  the  cylinder  is 
slowly  revolved;  the  plate  to  which  the  needle  is  attached  vi- 
brates to  correspond  with  the  voices  and  the  needle  gently  in- 
dents the  tin  foil,  striking  each  indentation  into  the  groove  of 
the  screw  so  that  it  is  clear  cut  and  visible,  though  very  small. 
The  speaking  having  been  concluded,  the  mouth-piece  is  swung 
away,  and  the  cylinder  is  screwed  back  to  where  it  began.  A 
large  tin  funnel  is  then  attached  to  the  mouth-piece,  which  is 
swung  back  to  the  cylinder.  This  funnel  is  designed  to  garner 
and  send  out  the  sounds  as  they  come  from  the  instrument;  the 
crank  is  turned,  and,  as  the  cylinder  moves  back  over  its  former 
course,  the  little  needle  strikes  into  the  indentations  first  made, 
thus  vibrating  the  tin  plate  of  the  mouth-piece  precisely  as  it 
was  vibrated  by  the  voice  and — lo  and  behold,  the  creature 
speaks !  That  is  all  there  is  to  it.  Its  voice  is  a  little  metallic, 
but  a  listener  can  recognize  a  friend's  eccentricity  of  speech. 
The  instrument  receives  a  tenor  or  treble  voice  much  more 
readily  than  a  bass.  Last  evening  the  instrument,  interviewed 
this  morning,  was  put  into  operation  in  the  auditorium  of  the 
First  Methodist  Church. 

"  Hurrah  for  Grant ! "  screamed  Mr.  Bliss,  forgetful  of  the  an- 
tiquity of  that  sentiment. 

"Hurrah  for  Grant!"  returned  the  instrument:  but  somebody 
had  laughed  at  Mr.  Bliss'  patriotic  exclamation.  So  the  machine 
laughed  while  getting  out  the  sentence,  in  such  a  manner  as 
would  not  have  sounded  really  flattering  to  the  ex-President 

It  repeated  with  the  real  spirit  and  twang  such  expressions  as 
"What  d'ye  soye?"  "Does  yer  mother  know  yer  out?"  and  num- 
berless other  Americanisms,  and,  at  length,  after  the  company 
had  been  speaking  very  loud,  under  the  irripression  that  the 
thing  had  to  be  very  emphatically  addressed,  the  little  daughter 
of  the  sexton  of  the  church  was  brought  into  requisition.  As 
it  happened,  she  was  bashful  and  could  only  be  gotten  to  speak 
very  low.  But  she  repeated  "  Mary  Had  a  Little  Lamb, "  and 
presently  the  instrument  ground  out  the  familiar  lines.  The 


AND  HIS  INVENTIONS.  85 

poem  being  encored,  Mr.  Bliss'  clerk  essayed  to  say  it,  but  the 
man  at  the  crank  turned  the  cylinder  with  increasing  speed,  so 
that  when  the  verses  were  returned,  the  tones  went  scaling  up 
in  rapidly  ascending  pitch,  until  at  last,  like  Elaine's  waitings, 
it  "scaled  high  on  the  last  line" — awful  high.  In  the  frequent 
repetitions  of  this  idyl,  it  was  not  observed  that  the  instrument 
ever  once  attempted  any  of  the  numerous  parodies  which  have 
been  perpetrated,  but  every  time  adhered  to  the  true  words  and 
meter,  from  which  it  may  be  inferred  that  it  will  be  a  truthful 
recorder. 


Phonographic  Records  under  the  Microscope. 

How  THE    LETTERS    LOOK— BELIEVED    BY    EDISON    TO  BE  LEG 
THE  DEEPEST  INDENTATIONS  MADE  BY  CONSONANTS. 

Microscopic  examination  of  the  indentations  made  in  the  tin  foil 
by  the  phonograph  when  spoken  to,  shows  that  each  letter  has  a 
definite  form,  though  there  is  a  great  variation,  resulting  from 
the  intensity  and  difference  of  voice.  Long  E  (or  ay)  on  the 
tin  foil  looks  like  two  indian  clubs  with  the  handles  together. 
The  same  general  resemblance  is  observed  in  E  short  except  that 
as  in  A  short,  the  volume  of  sound  being  less,  the  intensity  is 
less,  or  (what  is  the  measure  of  intensity)  the  path  of  the  needle- 
point is  shorter,  and  it  seldom  entirely  clears  the  foil,  the  conse- 
quence being  a  continuous  groove  of  irregular,  but  normally  ir- 
regular width. 

I  long  and  I  short  are  much  alike  in  general  form,  as  also  are 
O  long  and  O  short,  the  coupling  of  the  pairs  of  the  latter  being 
the  most  striking  feature.  U  long  and  U  short  best  show  the 
difference  in  shape  produced  by  less  intensities,  the  short 
being  drawn  out,  and  more  acicular. 

OI  is  very  interesting.  The  dipthong  consists  of  short  O  and 
short  I,  and  the  very  molds  which  characterize  their  sounds  are 
to  be  observed. 

OW  presents  a  composite  character,  but  its  derivation  has  not 


86  THOMAS  A.  EDISON 

yet  been  made  out.     Evidently  each  letter  has  a  definite  form. 

It  has  been  a  question  of  serious  consideration  and  one  of  great 
importance  with  Mr.  Edison  whether  the  indentations  in  the 
tin  foil  could  be  read  with  the  eye.  Want  of  time  has  kept 
him  from  making  extensive  experiments,  but  he  is  of  the  opinion 
that  careful  study  will  enable  experts  to  decipher  the  characters. 
Profs.  Fleming  Jenkin  and  M.  Ewing,  of  the  University  of  Glas- 
gow, Scotland,  have  spent  much  time  in  examining  the  phono- 
graphic records,  and  have  been  partially  successful  in  their 
attempts  to  read  them.  The  method  employed  by  the  Pro- 
fessors was  to  repeat  each  of  the  vowel  and  consonant  sounds 
a  number  of  times,  and  then  examine  the  record  to  determine 
if  the  indentation  had  any  regular  or  characteristic  shapes  which 
would  serve  to  identify  the  sounds.  The  result  shows  that  the 
record  of  any  single  sound  repeated  is  very  irregular — one  series 
of  indentation  differing  widely  from  another.  It  was  claimed, 
however,  that  despite  this  irregularity  the  record  of  any  one 
sound  could  be  distinguished  from  that  of  another  sound. 

Mr.  Edison  has  repeated  some  of  the  experiments  made  by 
Profs.  Jenkin  and  Ewing.  Knowing  beforehand  what  sounds 
had  produced  the  records,  he  could  tell  the  sounds  by  the  inden- 
tations and  also  count  the  number  of  times  a  sound  had  been 
repeated.  He  found  it  impossible,  however,  to  recognize  similar 
sounds  which  had  been  repeated  to  the  phonograph  by  another 
person.  The  shapes  of  the  indentations  were  found  by  experi- 
ments to  differ  for  the  same  sound,  according  to  the  speed  with 
which  the  cylinder  of  the  phonograph  was  turned,  the  force  with 
which  the  sound  was  uttered,  and  the  distance  of  the  mouth  from 
the  diaphragm.  Even  by  placing  his  hand  against  his  cheek 
while  repeating  the  sound,  Mr.  Edison  says  he  can  change  the 
shape  of  the  phonetic  characters.  The  depest  indentations  are 
made  by  consonant  sounds,  on  account  of  the  explosive  force 
with  which  these  sounds  are  uttered.  Words  beginning  with  P 
can  be  recognized  more  easily  than  any  others  by  the  deep  in- 
dentations which  begin  the  records.  One  difficulty  in  recog- 
nizing records  of  words  is  found  in  the  length  of  these  records. 


AND  HIS  INVENTIONS.  87 

The  clearness  of  the  phonograph's  articulation,  Mr.  Edison 
says,  depends  considerable  upon  the  size  and  shape  of  the  open- 
ing in  the  mouth-piece.  When  words  are  spoken  against  the 
whole  diaphragm,  the  hissing  sounds,  as  in  shall,  fleece,  etc.,  are 
tost.  These  sounds  are  rendered  clearly,  when  the  hole  is  small 
and  provided  with  sharp  edges,  or  when  made  in  the  form  of  a 
slot  surrounded  by  artificial  teeth. 

Besides  tinfoil,  other  metals  have  been  used.  Impressions 
have  been  made  upon  sheets  of  copper,  and  even  upon  soft 
iron.  With  the  copper  foil  the  instrument  spoke  with  sufficient 
force  to  be  heard  at  a  distance  of  two  hundred  and  seventy-five 
feet  in  the  open  air. 


Phonographic  Records  under  the  Microscope. 

In  the  above  engraving,  the  dotted  line  A,  represents  the  ap- 
pearance to  the  eye  of  the  impressions  made  on  the  foil  when 
the  sound  of  a  in  bat  is  sung  against  the  iron  plate  of  the  phono- 
graph. 

B,  is  a  magnified  profile  of  these  impressions  on  smoked  glass 
obtained  by  using  a  form  of  pantagraph. 

C,  gives  the   appearance   of  Konig"s   flame  when  the  same 
sound  is  sung  quite  close  to  its  membrane. 

It  will  be  seen  that  the  profile  of  the  impressions  made  on 
the  phonograph,  and  the  contours  of  the  flames  of  Konig,  when 
vibrated  by  the  same  compound  sound  bear  a  close  resemblance. 


88  THOMAS  A.  EDISON 

The  Phonograph  Supreme  at  Home. 

A  Western  journal  jocosely  remarks  that  the  phonograph  will 
be  a  source  of  comfort  and  consolation  to  long  suffering  wives 
whose  husbands  are  in  the  habit  of  staying  out  late  at  night  and 
returning  in  the  small  hours  to  wrestle  with  the  key-hole,  and 
eventually  go  to  bed  with  their  boots  on.  To  get  even  with 
these  wretches,  the  poor  woman  has  to  sit  up  and  await  their 
coming  in  order  to  more  effectually  free  her  mind.  Having  her 
phonograph,  she  can  speak  a  vigorous  lecture  into  it,  and,  fixing 
the  clock-work  so  that  it  will  go  off  at  the  time  she  knows  he 
will  return,  she  can  compose  herself  to  sleep,  confident  that  her 
representative  will  do  her  work  with  the  necessary  vigor  and  em- 
phasis, and  that  the  victim  will  have  to  endure  it.  He  may  raise 
the  window  and  pitch  the  phonograph  into  the  street,  but  the 
machine  will  none  the  less  have  its  say  out,  and  in  this  case  will 
have  the  immediate  neighbors  for  listeners.  For  the  curtain  lec- 
ture business  the  phonograph  will  be  of  great  advantage,  as  it 
can  be  set  to  go  off  at  any  specified  time,  like  an  alarm  clock. 
A  woman  specially  gifted  in  invective  and  sarcasm,  and  having  a 
good  flow  of  speech,  could  do  a  thriving  business  by  supplying 
plates  to  those  of  her  sex  less  gifted  in  the  science  of  combing 
down  recreant  spouses  and  reducing  them  to  a  state  of  pliability 
and  won't-do-so-any-more.  Many  family  jars  might  be  pleasant- 
ly adjusted  by  the  phonograph.  The  husband  and  wife  could 
scold  it  out  into  their  instruments,  and  leave  them  on  the  bureau 
for  the  housemaid  to  take  out  into  the  back-yard,  where  they 
could  splutter  at  each  other  without  doing  any  harm.  Right  at 
this  point,  however,  there  is  a  startling  possibility.  Mr.  Edison's 
aerophone  is  only  a  colossal  telephone  that  conveys  sound  for 
ten  miles.  The  alarming  capabilities  of  such  an  instrument  are 
apparent  when  the  reader  contemplates  an  irate  woman,  whose 
husband  is  out  later  than  he  ought  to  be,  in  possession  of  a  voice 
ten  miles  long  and  as  big  as  a  small  clap  of  thunder.  The  clock 
strikes  twelve,  one,  two;  the  whole  city  is  wrapped  in  silence, 
when  suddenly  a  voice  cries  through  the  startled  air,  awakening 


AND  HIS  INVENTIONS.  89 

every  one  from  sleep,  "John  Henry  Jones,  you  come  home  right 
off,  or  you'll  catch  it."  Such  developments  of  the  domestic 
discipline  are  among  the  alarming  possibilities  of  Mr.  Edison's 
inventions. 


"Uncle  Remus"  and  the  Phonograph. 

"Unc.  Remus,"  asked  a  tall,  awkward  looking  negro  who 
was  one  of  a  crowd  surrounding  the  old  man  in  front  of  James' 
Bank,  "Wat's  dis  'ere  wat  dey  calls  de  fongraf — dis 'ere  inst'u- 
ment  wa't  kin  holler  'roun  like  little  chillum  in  de  back  yard?" 

"I  ain't  seed  um,"  said  Uncle  Remus,  feeling  in  his  pocket 
for  a  fresh  chew  of  tobacco.  "I  ain't  seed  um,  but  I  hear  talk 
on  um.  Miss  Sally  wuz  a  readin'  in  de  papers  las'  Chuesday,  an' 
she  say  dat  it's  a  mighty  big  whatyoumaycallem. " 

"A  mighty  big  which?"  asked  one  of  the  crowd. 

"A  mighty  big  whatshisname,"  answered  Uncle  Remus.  "I 
wuzzent  up  dar  close  to  whar  Miss  Sa'ah  was  reedin'but  I  kinder 
geddered  it  in  dat  it  wuz  one  er  dese  'ere  whathisnamzes  Vat 
holler  inter  one  year  an'  it  comes  out  at  de  odder.  Hit's  mighty 
funny  unto  me  how  dese  folks  kin  go  an'  prognosticate  dere 
ekoes  intu  one  er  dese  yer  i'on  boxes,  an'  dar  hit'll  stay  ontwell 
de  man  comes  'long  an'  turns  de  handle  an'  lets  de  fuss  come 
pilin'  out,  Bimeby  dey'll  get  ter  makin'  shore-nuff  people,  an' 
den  dere'll  be  a  racket  'roun  here. — Dey  tells  me  dat  it  goes  off 
like  one  er  dese  'ere  torpedoes. " 

"You  hear  dat,  don't  you?"  said  said  one  or  two  of  the 
younger  negroes* 

"Dat's  w'at  dey  tells  me,"  continued  Uncle  Remus. — "Dat's 
w*at  dey  sez.  Hit's  one  er  dese  yer  kinder  Vatsiznames  dat 
sasses  back  when  you  hollers  at  it" 

"Wat  dey  fix  um  up  for  den?"  asked  one  of  the  practical 
negroes. 

"Dat's  w'at  I  want  er  know,"  said  Uncle  Remus  contempla- 
tively. "But  dat's  w'at  Miss  Sally  was  reedin'  in  de  paper.  All 


90  THOMAS  A.  EDISON 

you  gotter  do  is  holler  at  de  box,  an'  dar*s  no  remarks.  Dey 
goes  in,  an'  dar  dey  are  tooken,  an'  dar  dey  hangs  on  twell  you 
shake  de  box,  an'  den  dey  drops  out  des  er  dese  yere  fishes  w*at 
you  git  from  Savannah,  an'  you  ain't  got  time  fer  ter  look  at  dere 
gills  needer." 


Moses  and  the  Toddygraph. 

"Officer  Warlow  bring  up  Moses  in  the  'bulrushes,"  said  Jus- 
tice Bixby. 

The  officer  brought  up  a  seed-cucumbery  looking  individual, 
and  placed  him  at  the  railing. 

"The  officer  found  you  last  night, "  said  the  Judge,  lying  in 
the  bullrushes  round  the  Union  Square  fountain,  dead  drunk. 
What  have  you  to  sav?" 

Well,  Judge,  I'll  tell  you  how  it  was,"  said  the  prisoner,  I'm 
an  inventor. " 

"Of  what?"  asked  his  honor. 

"Of  thetoddygraph." 

"What's  that?" 

"Why,  you  wind  a  cylinder  with  tinfoil,''  said  the  prisoner, 
"and  drop  into  a  liquor-saloon  and  take  a  drink.  You  have  the 
cylinder  under  your  coat,  and  when  the  bar-keeper  ain't  looking, 
you  breathe  on  the  tinfoil;  when  you  get  out  you  turn  a  crank, 
and  repeat  the  drink  as  often  as  you  please. " 

"A  very  dangerous  invention, "  said  his  honor. 

"By  no  means,"  said  the  prisoner,  "for  it  ruins  the  landlord's 
business.  One  drink  will  last  a  week. " 

"Yes,"  said  his  Honor,  "but  it  kills  the  imbiber." 

"But  if  there  were  no  landlords  there  would  be  no  imbibers," 
said  the  prisoner. 

"That  may  be  so;  but  what  has  all  this  to  do  with  your  being 
found  drunk  in  a  public  park?" 

Til  tell  you.  Last  night  I  was  testing  a  new  machine,  and 
I  think — I  won't  be  positive — but  I  think  I  turned  the  crank 
just  once  too  often" 


AND  HIS  INVENTIONS.  91 

"Very  well,"  said  his  Honor,  "I  will  send  you  up  for  ten 
days. "  As  you  tarry  in  classic  Blackwell,  I  advise  you  to  turn 
your  inventive  genius  to  something  more  useful.  Invent  a  din- 
nergraph,  for  instance,  so  that  a  poor  man  can  repeat  a  square 
meal  often.  Millions  yet  unborn  will  bless  you,  and*  your  name 
will  go  down  to  posterity  along  with  Peter  Cooper  and  Florence 
Nightingale.  * 


How  the  "Phonograph  Man"  is  said  to  Amuse 
Himself. 

A  Cincinnati  gentleman  is  responsible  for  the  following: 

Edison,  the  phonograph  man,  is  wretched  unless  he  invents 
half  a  dozen  things  every  day.  He  does  it  just  for  amusement 
when  regular  business  isn't  pressing.  The  other  day  he  went 
out  for  a  little  stroll  and  he  thought  out  a  plan  for  walking  on 
one  leg  so  as  to  rest  the  other,  before  he  had  gone  a  square. 

He  hailed  a  milk-wagon  and  told  the  driver  of  a  little  inven- 
tion that  had  popped  through  his  head  just  that  moment  for 
delivering  milk  without  getting  out  of  his  wagon  or  even  stopping 
his  horses.  A  simple  force-pump,  with  hose  attached,  worked 
by  the  foot,  would  do  the  business.  Milk-men  who  dislike  to 
halt  for  anything  in  their  mad  career,  because  it  prevents  them 
running  over  as  many  children  as  they  might  otherwise  do, 
would  appreciate  this  improvement.  Edison  isn't  sure  but  that 
sausage  and  pig's  feet  could  be  delivered  in  the  same  way. 

He  stepped  into  a  hotel  office,  and,  observing  the  humiliations 
which  guests  encountered  in  seeking  to  obtain  information  from 
the  high-toned  clerk,  he  sat  down  in  the  reading-room,  and  in 
five  minutes  had  invented  a  hotel  clerk  to  work  by  machinery, 
warranted  to  stand  behind  the  counter  any  length  of  time  de- 
sired, and  answer  all  questions  with  promptness,  correctness, 
and  suavity— diamond  pin,  and  hair  parted  in  the  middle,  if 
desired. 

Lounging  into  the  billiard-room,  he  was  struck  with  the  need- 


92  THOMAS  A.  EDISON 

less  amout  of  cushions  required  to  each  table.  Quick  as  lighfning 
he  thought  of  a  better  and  more  economical  plan — cushion  the 
balls !  He  immediately  pulled  out  a  postal  card  and  wrote  to 
Washington  applying  for  a  patent 

When  Edison  started  to  go  out  he  had  to  pass  the  barber-shop 
of  the  hotel,  and,  as  he  did  so,  he  sighed  to  think  that,  with  all 
his  genius  and  creative  imagination,  he  could  never  hope  to 
equal  the  knight  of  the  razor  as  a  talking  machine.  This  saddened 
him  so  that  he  went  home  and  invented  no  more  that  day. 


How  the  Phonograph  Frightened  a  Preacher. 

One  of  the  most  amusing  anecdotes  in  relation  to  Mr.  Edison 
and  the  phonograph  is  told  in  connection  with  a  well  known 
divine  who  was  very  skeptical  concerning  the  capabilities  of  the 
wonderful  instrument  and  who,  it  seems,  had  a  vague  suspicion 
that  either  Mr.  Edison  or  some  one  of  his  assistants,  was  palm- 
ing off  some  first  class  ventiiloquism  under  the  assumed  name  of 
the  marvelous.  Such  a  remarkable  case  as  this  one  was  likely 
to  be,  Mr.  Edison  thought  demanded  special  attention  and  so  a 
plate  of  tin  foil  was  properly  doctored  for  the  divine,  to  suit  the 
emergency. 

Sure  enough  his  incredulity  was  manifested  at  the  proper  time. 
He  wanted  to  talk  into  the  mouthpiece  himself  and  see  if  his 
own  words  would  be  recorded  and  repeated.  So  down  he  sat 
and  gravely  repeated  a  verse  of  scripture  to  the  phonograph. — 
The  readjusment  was  made  and  to  his  utter  astonishment  it 
came  back  from  the  instrument  as  follows: 

He  that  cometh  from  above  is  above  all;  (who  are  you, 
anyhow?)  he  that  is  of  the  earth  (Oh,  pshaw,  give  us  a  rest,)  is 
earthly,  and  speaketh  of  the  (Look  here,  you  can't  preach,  go 
home)  earth,  etc.  The  startled  divine  was  lost  in  amazement, 
but  repeated  experiments  convinced  him  that  the  phonograph 
was  all  right 


AND  HIS  INVENTIONS.  93 

How  the  Phonograph  was  Discovered  by  Mr.  Edison. 

The  phonograph  was  discovered—  to  use  Mr.  Edison's  lan- 
guage— "by  the  merest  accident."  "I  was  singing,"  says  he,  "to 
the  mouthpiece  of  a  telephone,  when  the  vibrations  of  the  wire 
sent  the  fine  steel  point  into  my  finger.  That  set  me  to  thinking. 
If  I  could  record  the  actions  of  the  point,  and  then  send  the 
point  over  the  same  surface  afterwards,  I  saw  no  reason  why  the 
thing  would  not  talk. 

I  tried  the  experiment,  first  on  a  strip  of  telegraph  paper,  and 
found  that  the  point  made  an  alphabet.  I  shouted  the  word 
"Halloo!  Halloo!"  into  the  mouthpiece,  ran  the^paper  back  over 
the  steel  point  and  heard  a  faint  Halloo!  Halloo!  in  return !  I 
determined  to  make  a  machine  that  would  work  accurately,  and 
gave  my  assistants  instructions,  telling  them  what  I  had  dis- 
covered. 

They  laughed  at  me.  I  bet  fifteen  cigars  with  one  of  my 
assistants,  Mr.  Adams,  that  the  thing  would  work  the  first  time 
without  a  break,  and  won  them.  That's  the  whole  story.  The 
discovery  came  through  the  pricking  of  a  finger. " 

Mr.  Edison  related  this  story  of  the  phonograph's  origin  to  a 
company  of  interested  listeners  at  Menlo  Park,  as  given  above, 
and  then  turning  to  the  instrument  he  shouted  out  in  the  mouth- 
piece : 

"  Nineteen  years  in  the  Bastile  1 
I  scratched  a  name  upon  the  wall, 

And  that  name  was  Robert  Landry. 
Parlez  vous  Francais  ?  Si  habla  Espanol, 
Sprechen  sic  Deutsch  ?" 

And  the  words  were  repeated,  followed  by  the  air  of  "Old  Uncle 
Ned, "  which  he  had  sung. 


94  THOMAS  A.  EDISON 

Edison  Joking  with  the  Phonograph. 

The  matrix,  after  having  been  used  to  record  one  conversa- 
tion or  poem  as  the  case  may  be,  will  also  admit  of  another 
being  superinduced,  but  they  will,  of  course,  be  reported  in  a 
very  jumbling  manner.  In  this  way  Mr.  Edison  and  his  assist- 
ants frequently  created  much  amusement  for  the  listeners. 

On  one  occasion  the  affecting  words  of  the  first  verse  of  "Bin- 
gen  on  the  Rhine"  were  made  by  the  phonograph  to  be  reported 
as  follows: 

A  soldier  of  the  legion  lay  dying  in  algiers, 

"Oh,  shut  up!" "Oh,   bag  your  headl" 

There  was  lack  of  woman's   nursing,  there  was 

"Oh,  give  us  a  rest  1" 

lack  of  woman's  tears. 


—  "Dry  up!, 


But  a  comrade   stood  beside  him  while  his  life 
"Oh,  what  are  you  giving  us!" "Oh, 

blood  ebbed  away, 

cheese  it!" 

And  bent   with  pitying  glances  to  hear  what  he 
"Oh,  you  can't  read  poetry  1" "Let 

might  say. 

up!" 
The  dying  soldier  faltered,  and  he  took  that  com 

—  "Policel   Policel" "Po- 

rade's  hand, 

lice!" 
And  he  said,  "I  shall  never  see  my  own,  my 

—  "Oh,  put  him  outl" "Oh  cork 

native  land. " 

yourself! " 

It  is  impossible  to  describe  the  ludicrousness  of  the  effect  Mr. 
Edison  himself  laughed  like  a  boy. 


AND  HTS  INVENTIONS. 


95 


Edison's  Electric  Pen. 

Mr.  Edison  has  taught  the  lightning  to  write  in  more  ways 
than  by  chemistry.  Perhaps  his  most  simple,  and  still  very  ingen- 
ious, method  is  by  means  of  the  electric  pen,  over  sixty  thousand 
of  which  are  now  in  use  throughout  the  country.  The  electrici- 
ty in  this  case  causes  a  perforating  needle  point  to  move  up 
and  down  within  a  pencil  shaped  holder  at  very  great  rapidity. 
This  holder  is  manipulated  the  same  as  if  it  were  a  pen  or  pen- 
cil, and  as  it  moves  rapidly  over  the  surface  of  the  paper  the 
needle  point,  by  its  intensely  rapid  movement  perforates  the  pa- 


's  Electric  Pen. 

per  sufficiently  to  produce  a  perfect  stencil  of  what  has  been  writ- 
ten.— When  the  electric  writing  is  completed,  the  sheet  of  paper 
is  put  into  a  duplicating  press  and  copies  made  therefrom  in  any 
numbers  required.  The  perforations  are  so  numerous  and  so 
nearly  together,  that  when  the  ink  is  pressed  through  them  upon 
the  surface  of  the  duplicate  sheet,  they  seem  to  form  a  contin- 
uous line  making  the  writing  easily  legible,  provided  of  course, 
the  electric  instrument  which  makes  the  stencil  is  guided  by  a 
good  penman.  The  battery,  line,  pen,  and  working  principle 
of  this  novel  invention  are  shown  in  the  engraving  here  given. 


96  THOMAS  A.  EDISON 

The  Electro-Motograph. 

A  CURIOUS  INSTRUMENT— How  IT  WORKS— FOUR  HUNDRED  MOVES  IN 
ONE  SECOND  ! 

Among  the  most  singular  of  Mr.  Edison's  discoveries  is  the 
fact  that  certain  chemical  salts  lose  their  functional  properties 
when  subjected  to  the  action  of  an  electric  current.  On  this 
as  a  basis  of  action  he  has  devised  a  telegraphic  system  in  which 
the  ordinary  relay  magnet  is  wholly  unnecessary.  This  he  called 
the  Electro-motograph.  In  the  language  of  Mr.  Prescott,  "it 
was  the  substitution  of  friction  and  ante  friction  for  the  presence 
of  magnetism  in  the  relay.  It  was  remarkable  also,  in  that  it 
could  be  worked  by  an  almost  infinitessimal  current. "  Its  ra- 
pidity of  action  is  more  than  ten-fold  greater  than  any  magnet 
hitherto  constructed,  which  renders  it  the  only  known  apparatus 
that  can  repeat  or  translate,  from  one  circuit  to  another,  the 
signals  of  high  speed  telegraph  systems. 

The  working  principle  of  the  instrument  is  explained  as  fol- 
lows :  A  drum,  rotated  by  clock  work,  carries  slowly  forward  a 
slip  of  paper  moistened  with  a  solution  of  potassic  hydrate. — 
Immediately  over  this  drum  is  a  circuit  closing  lever  which 
moves  freely  upward  and  sideways.  Upon  the  extreme  end  of 
the  lever  is  a  screw  having  a  lead  point,  which  is  held  firmly 
against  the  surface  of  the  chemical  paper  by  the  tension  of  a 
spring.  Near  the  end  of  the  lever  is  a  platina  pointed  extension 
projecting  upwards,  its  extreme  end  playing  between  a  limiting 
screw  and  a  platina-pointing  screw  opposite.  The  local  connec- 
tions, or  second  line  wire  are  made  in  the  usual  manner.  There 
is  also  a  sounder  and  a  local  battery.  The  zinc  pole  of  the  main 
battery  is  connected  with  the  lead  point  screw,  while  the  other 
pole  is  connected  through  the .  key  to  the  drum.  The  action 
is  as  follows :  The  pressure  with  which  the  lead  point  is  held 
upon  the  chemical  paper  causes  great  friction  and  locks  the  point, 
as  it  were,  to  the  paper,  and  the  rotating  drum  carries  the  lever 
forward  to  the  limiting  screw,  the  local  circuit  and  main  line 
being  broken.  If  one  or  two  turns  only  be  given  the  spring 


AND  HIS  INVENTIONS.  97 

which  draws  the  lever  back,  the  friction  will  still  be  sufficient  to 
detain  the  lever  in  contact  with  the  drum,  but  the  moment  the 
key  is  closed,  the  passage  of  the  current  produces  an  unknown 
and  peculiar  action  upon  the  lead  point  and  chemical  paper,  and 
the  almost  total  annihilation  of  the  normal  friction,  when,  of 
course,  the  spring  draws  the  lever  back  and  closes  the  local  cir- 
cuit or  second  main  line  as  the  case  may  be,  and  continues 
there  as  long  as  the  current  passes;  but  when  the  current  is 
broken  by  the  key  the  normal  friction  returns  instantaneously, 
and  the  continuously  moving  drum  and  paper  carries  the  lever 
forward  again  to  the  limiting  screw,  or  stop,  breaking  the  sec- 
ondary circuit. 

The  genius  of  the  instrument  is  in  the  chemical  paper,  which 
in  some  strange  manner  loses  its  frictional  properties  when  sub- 
jected to  a  current  of  electricity.  By  means  of  signals  trans- 
mitted from  perforated  paper,  Mr.  Edison  succeeded  in  applying 
it  as  a  repeater,  and  transmitted  fourteen  hundred  words  from 
one  circuit  into  another  in  one  minute,  which  requires  at  least 
four  hundred  full  and  perfect  movements  of  the  lever  each 
second! 

Modifications  of  this  apparatus  have  been  devised  by  the  in- 
ventor, which  enables  it  to  work  with  positive  and  negative  cur- 
rents, thus  dispensing  with  the  adjusting  springs.  From  the  fact 
that  this  instrument  requires  but  small  battery  power  and  is 
remarkably  sensitive  to  feeble  currents,  and  can  be  used  to  record 
very  delicate  signals  without  electro-magnets,  it  is  extremely 
probable  that  it  will  be  the  basis  of  new  discoveries,  among 
which  is  the  solution  of  the  problem  of  fast  working  through 
long  sub-marine  cables.  "Important  results,"  says  Mr.  Prescott 
"are  to  follow  this  discovery." 


THOMAS  A.  EDISON 


Fig.  i.  Fig.  ». 

Tig.  i.   Carbon  Telephone— Interior.   A  A,  Iron  Diaphragm ;  B,  India  Rubber ;  C,  Ivory  ;D< 

Platina  Plate ;  E,  Carbon  Disk ;  G,  Platina  Screw.    Fig.  ».    Exterior 

View  of  Edison'i  Telephone. 

The  Telephone. 

EDISON'S  OWN  ACCOUNT  OF  His  DISCOVERY  OF  THE  CARBON  TELEPHONE — 
AN  INTERESTING  HISTORY — His  EXPLANATION  OF  THE  WONDER- 
FUL INSTRUMENT — ILLUSTRATED  BY  NUMEROUS  ENGRAV- 
INGS— IT  TALKS  OVER  A  WIRE  720  MILES 

LONG — His  OTHER  TELEPHONES. 

"My  first  attempt  at  constructing  an  articulating  telephone," 
says  Mr.  Edison,  ''was  made  with  the  Reiss  transmitter  and  one 
of  my  resonant  receivers,  and  my  experiments  in  this  direction, 
which  continued  until  the  production  of  my  present  carbon  tel- 
ephone, cover  many  thousand  pages  of  manuscript.  I  shall, 
however,  describe  here  only  a  few  of  the  more  important  ones. 

In  one  of  the  first  experiments  I  included  a  simplified  Reiss 
transmitter,  having  a  platinum  screw  facing  the  diaphragm,  in  a 
circuit  containing  twenty  cells  of  battery  and  the  resonant  re- 


AND  HIS  INVENTIONS.  99 

ceiver,  and  then  placed  a  drop  of  water  between  the  points;  the 
results,  however,  when  the  apparatus  was  in  action,  were  unsatis- 
factory— rapid  decomposition  of  the  water  took  place  and  a 
deposit  of  sediment  was  left  on  the  platinum.  I  afterwards  used 
disks  attached  both  to  the  diaphragm  and  to  the  screw,  with  sev- 
eral drops  of  water  placed  between  and  held  there  by  capillary 
attraction,  but  rapid  decomposition  of  the  water,  which  was 
impure,  continued,  and  the  words  came  out  at  the  receiver  very 
much  confused.  Various  acidulated  solutions  were  then  tried) 
but  the  confused  sounds  and  decompositions  were  the  only 
results  obtained. 

With  distilled  water  I  could  get  nothing,  probably  because,  at 
that  time,  I  used  very  thick  iron  diaphragms,  as  I  have  since 
obtained  good  results;  or,  possibly,  it  was  because  the  ear  was 
not  yet  educated  for  this  duty,  and  therefore  I  did  not  know 
what  to  look  for.  If  this  was  the  case,  it  furnishes  a  good  illus- 
tration of  the  fact  observed  by  Professor  Mayer,  that  we  often 
fail  to  distinguish  weak  sounds  in  certain  cases  when  we  do  not 
know  what  to  expect. 

Sponge,  paper  and  felting,  saturated  with  various  solutions, 
were  also  used  between  the  disks,  and  knife  edges  were  substi- 
tuted for  the  latter  with  no  better  results.  Points  immersed 
in  electrolytic  cells  were  also  tried,  and  the  experiments  with 
various  solutions,  devices,  etc.,  continued  until  February,  1876, 
when  I  abandoned  the  decomposable  fluids  and  endeavored 
to  vary  the  resistance  of  the  circuit  proportionately  with  the  am- 
plitude of  vibration  of  the  diaphragm  by  the  use  of  a  multipli- 
city of  platinum  points,  springs  and  resistance  coils — all  of  which 
were  designed  to  be  controlled  by  the  movements  of  the  dia- 
phragm, but  none  of  the  devices  were  successful. 

In  the  spring  of  1876,  and  during  the  ensuing  summer,  I  en- 
deavored to  utilize  the  great  resistance  of  thin  films  of  plumbago 
and  white  Arkansas  oil  stone,  on  ground  glass,  and  it  was  here 
that  I  first  succeeded  in  conveying  over  wires  many  articulated 
sentences.  Springs  attached  to  the  diaphragm  and  numerous 
other  devices  were  made  to  cut  in  and  out  of  circuit  more  or  less 


ioo  THOMAS  A.  EDISON 

of  the  plumbago  film,  but  the  disturbances  which  the  devices 
themselves  caused  in  the  true  vibrations  of  the  diaphragm  pre- 
vented the  realization  of  any  practical  results.  One  of  my  as- 
sistants, however,  continued  the  experiments  without  interruption 
until  January,  1877,  when  I  applied  the  peculiar  property  which 
semi-conductors  have  of  varying  their  resistance  with  pressure, 
a  fact  discovered  by  myself  in  1873,  wnu<e  constructing  some 
rheostats  for  artificial  cables,  in  which  were  employed  powdered 
carbon,  plumbago  and  other  materials,  in  glass  tubes. 

For  the  purpose  of  making  this  application,  I  constructed  an 
apparatus  provided  with  a  diaphragm  carrying  at  its  centre  a 
yielding  spring,  which  was  faced  with  platinum,  and  in  front  of 
this  I  placed,  in  a  cup  secured  to  an  adjusting  screw,  sticks  of 
crude  plumbago,  combined  in  various  proportions  with  dry  pow- 
ders, resins,  etc.  By  this  means  I  succeeded  in  producing  a 
telephone  which  gave  great  volume  of  sound,  but  its  articula- 
tion was  rather  poor;  when  once  familiar  with  its  peculiar  sound, 
however,  one  experienced  but  little  difficulty  in  understanding 
ordinary  conversation. 

After  conducting  a  long  series  of  experiments  with  solid  ma- 
terials, I  finally  abandoned  them  all  and  substituted  therefor 
tufts  of  conducting  fibre,  consisting  of  floss  silk  coated  with 
plumbago  and  other  semi-conductors.  The  results  were  then 
very  much  better,  but  while  the  volume  of  sound  was  still  great, 
the  articulation  was  not  so  clear  as  that  of  the  magneto  tele- 
phone of  Prof.  Bell.  The  instrument,  besides,  required  very 
frequent  adjustment,  which  constituted  an  objectionable  feature. 

Upon  investigation,  the  difference  of  resistance  produced  by 
the  varying  pressure  upon  the  semi-conductor  was  found  to  be 
exceedingly  small,  and  it  occurred  to  me  that  as  so  small  a 
change  in  a  circuit  of  large  resistance  was  only  a  small  factor,  in 
the  primary  circuit  of  an  induction  coil,  where  a  slight  change  of 
resistance  would  be  an  important  factor,  it  would  thus  enable 
me  to  obtain  decidedly  better  results  at  once.  The  experiment, 
however,  failed,  owing  to  the  great  resistance  of  the  semi-con- 
ductors then  used 


AND  HIS  INVENTIONS.  101 

After  further  experimenting  in  various  directions,  I  was  led  to 
believe,  if  I  could  by  any  means  reduce  the  normal  resistance 
of  the  semi-conductor  to  a  few  ohms,  and  still  effect  a  difference 
in  its  resistance  by  the  pressure  due  to  the  vibrating  diaphragm, 
that  I  could  use  it  in  the  primary  circuit  of  an  induction  coil. — 
Having  arrived  at  this  conclusion,  I  constructed  a  transmitter  in 
which  a  button  of  some  semi-conducting  substance  was  placed 
between  two  platinum  disks,  in  a  kind  of  cup  or  small  containing 
vessel.  Electrical  connection  between  the  button  and  disks  was 
maintained  by  the  slight  pressure  of  a  piece  of  rubber  tubing, 
^  inch  in  diameter  and  j^  inch  long,  which  was  secured  to  the 
diaphragm,  and  also  made  to  rest  against  the  outside  disk.  The 
vibrations  of  the  diaphragm  were  thus  able  to  produce  the  re- 
quisite pressure  on  the  the  platinum  disk,  and  thereby  vary  the 
resistance  of  the  button  included  in  primary  circuit  of  the  induc- 
tion coil. 

At  first  a  button  of  solid  plumbago,  such  as  is  employed  by 
clectrotypers,  was  used,  and  the  results  obtained  were  considered 
excellent,  everything  transmitted  coming  out  moderately  distinct, 
but  the  volume  of  sound  was  no  greater  than  that  of  the  mag- 
neto telephone. 

In  order,  therefore,  to  obtain  disks  or  buttons,  which,  with  a 
low  normal  resistance,  could  also  be  made,  by  a  slight  pressure, 
to  vary  greatly  in  this  respect,  I  at  once  tried  a  great  variety  of 
substances,  such  as  conducting  oxides,  sulphides  and  other  par- 
tial conductors,  among  which  was  a  small  quantity  of  lampblack 
that  had  been  taken  from  a  smoking  petroleum  lamp  and  pre- 
served as  a  curiosity  on  account  of  its  intense  black  color. 

A  small  disk  made  of  this  substance,  when  placed  in  the  tele- 
phone, gave  splendid  results,  the  articulation  being  distinct,  and 
the  volume  of  sound  several  times  greater  than  with  telephones 
worked  on  the  magneto  principle.  It  was  soon  found  upon  in- 
vestigation, that  the  resistance  of  the  disk  could  be  varied  from 
three  hundred  ohms  to  the  fractional  part  of  a  single  ohm  by 
pressure  alone,  and  that  the  best  results  were  obtained  when  the 
resistance  of  the  primary  coil,  in  which  the  carbon  disk  was  in- 


102  THOMAS  A.  EDISON 

eluded,  was  six-tenths  of  an  ohm,  and  the  normal  resistance  of 
the  disk  itself  three  ohms. 

Mr.  Henry  Bentley,  President  of  the  Local  Telegraph  Com- 
pany, at  Philadelphia,  who  has  made  an  exhaustive  series  of  ex- 
periments with  a  complete  set  of  this  apparatus  upon  the  wires 
of  the  Western  Union  Telegraph  Company,  has  actually  suc- 
ceeded in  working  with  it  over  a  wire  of  720  miles  in  length, 
and  has  found  it  a  practicable  instrument  upon  wires  of  100  to 
200  miles  in  length,  notwithstanding  the  fact  that  the  latter  were 
placed  upon  poles  with  numerous  other  wires,  which  occasioned 
sufficiently  powerful  induced  currents  in  them  to  entirely  destroy 
the  articulation  of  the  magneto  telephone.  I  also  learn  that  he 
has  found  the  instrument  practicable,  when  included  in  a  Morse 
circuit,  with  a  battery  of  eight  or  ten  stations  provided  with  the 
ordinary  Morse  apparatus;  and  that  several  way  stations  could 
exchange  business  telephonically  upon  a  wire  which  was  being 
worked  with  a  quadruplex  without  disturbing  the  latter,  and  not- 
withstanding, also,  the  action  of  the  powerful  reversed  currents 
of  the  quadruplex  on  the  diaphragms  of  the  receiver.  It  would 
thus  seem  as  though  the  volume  of  sound  produced  by  the  voice 
with  this  apparatus  more  than  compensates  for  the  noise  caused 
by  such  actions. 

While  engaged  in  experimenting  with  my  telephone  for  the 
purpose  of  ascertaining  whether  it  might  not  be  possible  to  dis- 
pense with  the  rubber  tube  which  connected  the  diaphragm  with 
the  rheostatic  disk,  and  was  objectionable  on  account  of  its  ten- 
dency to  become  flattened  by  continued  vibrations,  and  thus 
necessitate  the  readjustment  of  the  instrument,  I  discovered 
that  my  principle,  unlike  all  other  acoustical  devices  for  the 
transmission  of  speech,  did  not  require  any  vibration  of  the 
diaphragm — that,  in  fact,  the  sound  waves  could  be  transformed 
into  electrical  pulsations  without  the  movement  of  any  interven- 
ing mechanism. 

The  manner  in  which  I  arrived  at  this  result  was  as  follows : — 
I  first  substituted  a  spiral  spring  of  about  a  quarter  inch  in 
length,  containing  four  turns  of  wire,  for  the  rubber  tube  which 


AND  HIS  INVENTIONS.  103 

connected  the  diaphragm  with  the  disks.  I  found,  however, 
that  this  spring  gave  out  a  musical  tone,  which  interfered  some- 
what with  the  effects  produced  by  the  voice;  but,  in  the  hope 
of  overcoming  the  defect,  I  kept  on  substituting  spiral  springs  of 
thicker  wire,  and  as  I  did  so  I  found  that  the  articulation  became 
both  clearer  and  louder.  At  last  I  substituted  a  solid  substance 
for  the  springs  that  had  gradually  been  made  more  and  more 
inelastic,  and  then  I  obtained  very  marked  improvements  in  the 
results.  It  then  occurred  to  me  that  the  whole  question  was  one 
of  pressure  only,  and  that  it  was  not  necessary  that  the  dia- 
phragm should  vibrate  at  all.  I  consequently  put  in  a  heavy 
diaphragm,  one  and  three  quarter  inches  in  diameter  and  one 
sixteenth  inch  thick,  and  fastened  the  carbon  disk  and  plate 
tightly  together,  so  that  the  latter  showed  no  vibration  with  the 
loudest  tones.  Upon  testing  it  I  found  my  surmises  verified ; — 
the  articulation  was  perfect,  and  the  volume  of  sound  so  great 
that  conversation  carried  on  in  a  whisper  three  feet  from  the  tel- 
ephone was  clearly  heard  and  understood  at  the  other  end  of  the 
line.  This,  therefore,  is  the  arrangement  I  have  adopted  in  my 
present  form  of  apparatus,  which  I  call  the  carbon  telephone,  to 
distinguish  it  from  others. 

The  accessories  and  connections  of  this  apparatus  for  long 
circuits  are  shown  in  Fig.  3.  A  is  an  induction  coil,  whose 
primary  wire,  P,  having  a  resistance  of  several  ohms,  is  placed 
around  the  secondary,  instead  of  within  it  as  in  the  usual  man- 
ner of  construction.  The  secondary  coil,  s,  of  finer  wire, 
has  a  resistance  of  from  150  to  200  ohms,  according  to  the  de- 
gree of  tension  required;  and  the  receiving  telephone,  R.  con- 
sists simply  of  a  magnet,  coil,  and  diaphragm.  One  pole  of  the 
magnet  is  connected  to  the  outer  edge  of  the  diaphragm,  and 
the  other^  which,  carries  the  wire  bobbin  of  about  77  ohms  re- 
sistance, and  is  included  in  the  main  line,  is  placed  just  op- 
posite its  center. 

"P  R.  is  the  signaling  relay,  the  lever  of  which,  when  actuated 
by  the  current  from  a  distant  station  on  the  line  in  which  the  in- 
strument is  included,  closes  a  local  circuit  containing  the  vibra- 


io4  THOMAS  A.  EDISON 

ting  call  bell,  B,  and  thus  gives  warning  when  speaking  com- 
munication is  desired. 

"Besides  serving  to  operate  the  call  bell,  the  local  battery,  E, 
is  also  used  for  sending  the  call  signal. .  S  is  a  switch,  the  lever 
of  .which,  when  placed  at  0,  between  m,  and  n,  disconnects  the, 
transmitter,  T,  and  local  battery,  E,  from  the  coil,  A,  and  in  this 
position  leaves  this  polarized  relay,  P  R,  free  to  respond  to  cur- 
rents from  the  distant  station.  When  this  station  is  wanted,  how- 


fig.  3;  Telephone  Apparatus. 

ever,  the  lever,  S,  is  turned  to  the  left  on  n,  and  depressed  sev- 
eral times  in  rapid  succession.  The  current  from  the  local  bat- 
tery, by  this  means,  is  made  to  pass  through  the  primary  coil 
of  A,  and  thus  for  each  make  and  brake  of  the  circuit  induces 
powerful  currents  in  the  secondary,  s,  which  pass  into  the  line 
and  actuate  the  distant  call  bell. 

"When  the  call  signals  have  been  exchanged,  both  terminal 
stations  place  their  switches  to  the  right  on  m,  and  thus  intro- 
duce the  carbon  transmitter  into  their  respective  circuits.  The 


AND  HIS  INVENTIONS.  105 

changes  of  pressure  produced  by  speaking  against  the  diaphragm 
of  either  transmitter,  then  serve,  as  already  shown,  to  vary  the 
resistance  of  the  carbon,  and  thus  produce  corresponding  varia- 
tions in  the  induced  currents,  which,  acting  through  the  re- 
ceiving instrument,  reproduce  at  the  distant  station  whatever 
has  been  spoken  into  the  transmitting  instrument. 

For  lines  of  moderate  lengths,  say  from  one  to  thirty  miles, 
another  arrangement,  shown  in  Fig,  4,  may  be  used  advantage- 


Fig.  4;  Telephone  Apparatus,  with  Switch. 

ously.  The  induction  coil,  key,  battery,  and  receiving  and 
transmitting  telephones,  are  lettered  the  same  as  in  the  previous 
engraving,  and  are  similar  in  every  respect  to  the  apparatus 
there  shown ;  the  switch,  S,  however,  differs  somewhat  in  con- 
struction from  the  one  already  described,  but  is  made  to  serve  a 
similar  purpose.  When  a  plug  is  inserted  between  3  and  4  the 
relay  or  sounder,  R,'  battery  E,  and  key,  K,  only  are  included 
in  the  main  line  circuit,  and  this  is  the  noimal  arrangement  of  the 
apparatus  for  signaling  purposes.  The  battery,  usually  about 


106  THOMAS  A.  EDISON 

three  cells  of  the  Daniell  form,  serves  also  both  for  a  local  and 
main  battery.  When  a  plug  is  inserted  between  i,  2,  and  4,  the 
apparatus  is  available  for  telephonic  communication. 

I  have  also  found,  on  lines  of  from  one  to  twenty  miles  in 
length,  that  the  ordinary  call  can  be  dispensed  with,  and  a  sim- 
plified arrangement  substituted.  This  latter  consists  simply  of 
the  ordinary  receiving  telephone,  upon  the  diaphram  of  which  a 
free  lever,  L,  is  made  to  rest,  as  shown  in  Fig.  5.  When  the  in- 
duced currents  from  the  distant  station  act  upon  the  receiver, 
R,  the  diaphgram  of  the  latter  is  thrown  into  vibration,  but  by 
itself  is  capable  of  giving  only  a  comparatively  weak  sound; 
with  the  lever  resting  upon  its  center,  however,  a  sharp,  pene- 


Fig.  5 ;  Lever  Signal. 

trating  noise  is  produced  by  the  constant  and  rapid  rebounds  of 
the  lever,  which  thus  answers  veiy  well  for  calling  purposes  at 
stations  where  there  is  comparatively  but  little  noise. 

Among  the  various  other  methods  for  signalling  purposes 
which  I  have  experimented  with,  I  may  mention  the  sounding 
of  a  note,  by  the  voice,  in  a  small  Reiss's  telephone;  the  employ- 
ment of  a  self-vibrating  reed  in  the  local  circuit;  and  a  break 
wheel  with  many  cogs,  so  arranged  as  to  interrupt  the  circuit 
when  set  in  motion. 

I  have  also  used  direct  and  induced  currents  to  release  clock 
work,  and  thus  operate  a  call,  and  in  some  of  my  earlier  acoustic 
experiments  tuning  forks  were  used,  whose  vibrations  in  front- 
of  magnets  caused  electrical  currents  to  be  generated  in  the  coils 
surrounding  the  latter. 


AND  HIS  INVENTIONS.  107 

By  the  further  action  of  these  currents  on  similar  forks  at  a 
distant  station,  bells  were  caused  to  be  rung,  and  signals  thus 
given.  Fig.  6  shows  an  arrangement  of  this  kind.  A  and  R 


Fig.  6;  Tuning  Fork  Signal. 

are  two  magnetized  tuning  forks,  having  the  same  rate  of 
vibration  and  placed  at  two  terminal  stations.  Electro-magnets 
m  and  m1  are  placed  opposite  one  of  the  prongs  of  the  forks  at 
each  station,  while  a  bell,  C  or  D,  stands  opposite  to  the  other. 
The  coils  of  the  magnet  are  connected  respectively  to  the  line 
wire  and  to  earth.  When  one  of  the  forks  is  set  in  vibration  by 
a  starting  key  provided  for  the  purpose,  the  currents  produced 
by  the  approach  of  one  of  its  magnetized  prongs  towards  the 


Fig.  7 ;  Pendulum  Signal. 

magnet,  and  its  recession  therefrom,  pass  into  the  line  and  to  the 
further  stations  where  their  action  soon  causes  the  second  fork 
to  vibrate  with  constantly  increasing  amplitude,  until  the  bell  is 
struck  and  the  signal  given. 


io8  THOMAS  A.  EDISON 

For  telephonic  calls  the  call  bells  are  so  arranged  that  the  one 
opposite  to  the  fork,  which  generates  the  currents,  is  thrown  out 
of  the  way  of  the  latter's  vibrations. 

Another  call  apparatus  which  I  have  used,  is  represented  in 
Fig.  7.  In  this  arrangement  two  small  magnetic  pendulums, 
whose  rates  of  vibration  are  the  same,  are  placed  in  front  of 
separate  electro-magnets,  the  helices  of  which  join  in  the  main 
line  circuit.  When  one  of  the  pendulums  is  put  in  motion,  the 
currents  generated  by  its  forward  and  backward  swings  in  front 
of  the  electro-magnet  pass  into  the  line,  and  at  the  opposite  ter- 
minal, acting  through  the  helix  there,  cause  the  second  pendu- 
lum to  vibrate  in  unison  with  the  former. 


Fig.  8  ;  Electrophons  Telephone. 

Fig.  8  shows  a  form  of  electrophorus  telephone  which  acts  by 
the  approach  of  the  diaphragm  contained  in  A  or  B  towards,  or 
its  recession  from,  a  highly  charged  electrophorus,  C  or  D. 
The  vibrations  of  the  transmitting  diaphragm  cause  a  disturbance 
of  the  charge  at  both  ends  of  the  line,  and  thus  give  rise  to 
faint  sounds.  Perfect  insulation,  however,  is  necessary,  and 
either  apparatus  can  be  used  both  for  transmitting  and  re- 
ceiving, but  the  results  are  necessarily  very  weak. 

Another  form  of  electro-static  telephone  is  shown  in  Fig.  9. — 
In  this  arrangement  Deluc  piles  of  some  20,000  disks  each  are 
contained  in  glass  tubes,  A  and  B.,  and  conveniently  mounted 
on  glass,  wood,  or  metal  stands.  The  diaphragms,  which  are  in 
electrical  connection  with  the  earth,  are  also  placed  opposite  to 
one  pole  of  each  of  the  piles,  while  the  opposite  poles  are  joined 
together  by  the  line  conductor.  Any  vibration  of  either  dia- 
phragm is  thus  capable  of  disturbing  the  electrical  condition  of 


AND  HIS  INVENTIONS. 


109 


the  neighboring  disks,  the  same  as  in  the  electrophorus  tele- 
ephones;  and  consequently  the  vibrations,  when  produced  by 
the  voice  in  one  instrument,  will  give  rise  to  corresponding  elec- 


F!g.  9;  Electro-Static  Telephone. 

trical  changes  in  the   other,    and   thereby  reproduce  in  it  what 
has  been  spoken  into  the  mouthpiece  of  the  former. 

With  this  arrangement  fair  results  may  be  obtained,  and  it  is 
not  necessary  that  the  insulation  should  be  so  perfect  as  for  tbf-, 
electrophorus  apparatus. 


Fig.  10 ;  Electro-Mechanical  Telephone. 

Kg.  10  shows  a  form  of  electro-mechanical  telephone,  by 
means  of  which  I  attempted  to  transmit  electrical  impulses  of 
various  strength  so  as  to  reproduce  spoken  words  at  a  distance. 
Small  resistance  coils  (i,  2,  3,  etc.)  were  so  arranged  with  con- 
necting springs  near  a  platinum  faced  lever,  B,  in  connection 
with  the  diaphragm  in  A,  that  any  movement  of  the  latter  caused 
one  or  more  of  the  coils  to  be  cut  in  or  out  of  the  primary  cir- 
cuit of  an  induction  coil,  C,  the  number,  of  course,  varying 
with  the  amplitude  of  the  vibrating  diaphragm.  Induced  cur- 
rents corresponding  in  strength  with  the  variations  of  resistance 
were  thus  sent  into  the  line,  and  could  then  be  made  to  act 


izo  THOMAS  A.  EDISON 

upon  an  ordinary  receiving  telephone.  By  arranging  the  springs 
in  a  sunflower  pattern  about  a  circular  lever,  articulate  sentences 
have  been  transmitted  by  this  method,  but  the  results  were  very 
harsh  and  disagreeable. 

Fig.  ii  shows  a  form  of  the  water  telephone,  in  which  a 
double  cell  was  used  so  as  to  afford  considerable  variation  of  re- 
sistance for  the  very  slight  movements  of  the  diaphragm.  The 
action  of  the  apparatus  will  readily  be  understood  from  the  en- 


rig,  n;  Water  Telephone. 

graving,  where  a  wire  in  the  form  of  the  letter  U  is  shown, 
with  the  bend  attached  to  the  diaphragm,  and  its  ends  dipping 
into  the  separate  cells,  and  thus  made  to  form  part  of  the  cir- 
cuit when  the  line  is  joined  to  the  instrument  at  a  and  c. 

I  am  now  conducting  experiments  with  a  thermo-electric  tele- 
phone, which  gives  some  promise  of  becoming  serviceable.  In 
this  arrangement  a  sensitive  thermo-pile  is  placed  in  front  of  a 
diaphragm  of  vulcanite  at  each  end  of  a  line  wire,  in  the  circuit 
of  which  are  included  low  resistance  receiving  instruments.  The 
principle  upon  which  the  apparatus  works  depends  upon  the 
change  of  temperature  produced  in  the  vibrating  diaphragm, 
which  I  have  found  is  much  lower  as  the  latter  moves  forward, 
and  is  also  correspondingly  increased  on  the  return  movement. 

Sound  waves  are  thus  converted  into  heat  waves  of  similar 
characteristic  vanations,  and  I  am  in  hopes  that  I  may  ultimately 
be  able,  by  the  use  of  more  sensitive  thermo -piles,  to  transform 
these  heat  waves  into  electrical  currents  of  sufficient  strength  to 
produce  a  practical  telephone  on  this  novel  principle. 

Before  concluding,   I  must  mention  an  interesting  fact  con- 


AND  HIS  INVENTIONS.  in 

nected  with  telephonic  transmission,  which  was  discovered  during 
some  of  my  experiments  with  the  magneto-telephone,  and  which 
is  this,  that  a  copper  disk  may  be  substituted  for  the  iron  dia- 
phragm now  universally  used.  The  same  fact,  I  believe,  has 
also  been  announced  by  Mr.  W.  H.  Preece,  to  the  Physical 
Society  at  London. 

If  a  piece  of  copper,  say  one  sixteenth  of  an  inch  thick  and 
three  fourths  of  an  inch  in  diameter,  is  secured  to  the  center  of 
a  vulcanite  diaphragm,  the  effect  becomes  quite  marked,  and  the 
apparatus  is  even  more  sensitive  than  when  the  entire  diaphragm 
is  of  copper.  The  cause  of  the  sound  is  due,  no  doubt,  to  the 
production  of  very  weak  electrical  currents  in  the  copper  disk. 

It  will  be  seen  from  this  description  by  Mr.  Edison  that  the 
carbon  telephone  was  not  the  work  of  a  single  day  but  of  years, 
in  which  he  labored  with  singular  patience  and  tenacity.  The 
genius  of  the  instrument  is  the  carbon  button.  This  is  the  all 
essential  factor,  not  only  in  the  telephone,  but  in  the  tasimeter, 
and  other  inventions  of  Mr.  Edison.  It  ranks  among  the  grand- 
est discoveries  of  the  nineteenth  century.  With  the  appliances 
already  completed  it  is  possible  that  a  thunder-clap  might  be 
made  to  roll  around  the  world,  and  in  the  near  future,  greater 
results  will  certainly  come  to  pass.  By  this  same  marvelous 
button  in  the  tasimeter,  the  heat  of  a  telescopic  star  is  definitely 
registered,  and  yet  the  nearest  fixed  star  is  over  thirty  trillions 
of  miles  distant  from  the  earth.  If  not  the  philosopher's  stone,  it 
is  certainly  next  to  it,  in  its  wonderful  facilities  for  transforma- 
tions. 

Mr.  Edison  has  very  recently  invented  a  new  telephone 
receiver,  in  which  no  magnet  is  used.  It  is  based  upon  the  the 
principle  of  the  electro-motograph,  described  elsewhere  in  this 
volume.  By  this  new  receiver  the  volume  of  the  message  trans- 
mitted is  increased  so  as  to  be  heard  distinctly  fifteen  feet  from 
the  instrument.  It  is  expected  this  new  invention  will  render 
possible  conversation  through  the  Atlantic  cable,  and  that  be- 
tween the  large  cities  throughout  the  country  this  will  be  a  daily 
occurrence.  He  is  also  introducing  a  "double  transmitter." 


xi2  THOMAS  A.  EDISON 

Testing   Edison's  Telephone. 

A  LITTLE  CHAT,  INTERMINGLED  WITH  WHISPERS,  BETWEEN  PERSONS  210 

MILES  APART— AN  INNOCENT  JOKE  PERPETRATED  ON  MR. 

FIRMAN — COMPLETE  SUCCESS  OF  THE 

CARBON  TELEPHONE. 

A  thorough  and  satisfactory  test  of  Edison's  Telephone  was 
made  January  5th,  1879,  over  a  wire  of  the  Western  Union  Tel- 
egraph company  between  Indianapolis  and  Chicago.  The  wire 
runs  along  the  I.  C.  &  L.  Railroad  to  Lafayette;  thence  along 
the  N.  A.  &  C.  Railroad  to  Wanatah;  thence  along  the  P.  Ft. 
W.  &  C.  Railroad  to  Chicago,  being  about  two  hundred  and 
ten  miles  in  length.  When  the  reporter,  whose  account  we  here 
give,  entered  the  Superintendent's  rooms  at  the  Indianapolis 
end,  the  experiment  had  already  begun  and  almost  the  first  thing 
he  heard  was  the  operator  at  that  end,  speaking  in  the  telephone, 
saying:  "Here  comes  a.  Journal  man.  Wait  till  I  give  him  a  re- 
ceiver, so  he  can  hear  you." 

Another  receiving  telephone  was  attached  and  handed  to  the 
visitor,  when  the  operator  said,  "Now,  Mr.  Wilson,  at  Chicago, 
I  want  to  introduce  Mr.  Blank,  of  the  Journal,  at  Indianapolis. 
Speak  to  him.  He  is  listening.  Be  careful  how  you  talk,  he  is 
liable  to  print  it. " 

Instantly  came  back,  clear  and  distinct,  as  if  spoken  through 
a  tube  from  an  adjoining  room,  "Good  morning,  Mr.  Blank.  I 
hope  you  are  very  well.  Are  you  able  to  understand  me?" 

"Perfectly,"  was  the  reply;  "and  I  can  hardly  believe  you  are 
so  far  away. " 

"If  you  were  acquainted  with  my  voice,  so  as  to  recognize  it, 
your  belief  would  be  strengthened. " 

"Yes,  very  likely.  I  can  see  that  if  I  were  acquainted  with 
your  voice,  I  could  easily  recognize  it.  Have  you  ever  talked 
this  far  before?" 

"Oh,  yes,  we  had  a  chat  with  your  Indianapolis  friends  two  or 
three  Sundays  ago,  which  was  very  satisfactory.  We  even  ex- 
changed whispers  that  day.  Lef  s  try  it  now.  Listen  closely. " 


AND  HIS  INVENTIONS.  113 

A  whisper  sound  was  heard.  When  notified  that  ten  would 
be  counted  it  was  readily  recognized  in  a  whisper. 

Mr.  Smith,  of  the  W.  U.  T.  Company,  then  stepped  to  the 
instrument  and  spoke  to  Mr.  Wilson,  at  Chicago. 

"Good  morning,  Charlie." 

"Good  morning,  Mr.  Smith." 

"You  know  me,  do  you?" 

"Why,  of  course  I  do.     Pretty  cold  morning,  this. " 

"Pretty  cool  here;  we  are  getting  used  to  it  though.  The  wire 
works  nicely,  don't  it?" 

"Yes,  indeed,  couldn't  ask  anything  better. 

"Say,  Charlie?" 

"Well. " 

"Have  you  a  wire  over  to  the  Telephone  Exchange?" 

"Yes,  sir." 

"See  if  you  can  find  Mr.  Firman  at  his  office  or  his  house,  and 
connect  that  wire  to  this. " 

"All  right.     Guess  I  can  find  him  in  a  few  minutes." 

"Just  say  that  some  one  wants  to  speak  with  him,  but  don't 
say  who  or  where. " 

"All  right;  we'll  have  some  fun  with  the  gentleman  if  I  can 
find  him.  I'll  call  you;  look  out  for  me. " 

"All  right."    ' 

Mr.  Firman  is  the  General  Manager  of  the  Telephone  Ex- 
change and  American  District  Telegraph  Company  in  Chicago. 
After  waiting  perhaps  three  minutes,  Mr.  Wilson's  voice  was 
heard: 

"Mr.  Firman's  at  home.  I'm  going  to  connect  you.  Speak 
to  him.  Now!" 

"Halloo,  Firman  1" 

"Halloo,  yourself!    What  do  you" want?" 

"Well,  I  wanted  to  say  good  morning,  but  you  seem  a  little 
bit  crusty,  so  I  won't." 

"Well,  I  take  it  all  back.  I'm  glad  to  see  you.  How  are  you, 
any  how?  When  did  you  come  to  town?" 

"Guess  you  don't  know  who  you  are  talking  to." 
8 


H4  THOMAS  A.  EDISON 

Tm  talking  to  Wiley  Smith,  or  I'm  very  much  mistaVen.* 

"You  are  right     Thought  I  would  beat  you  this  time. " 

"Oh,  no!  my  telephone  experience  has  enabled  me  to  recall 
familiar  voices  without  many  mistakes  now.  Where  are  you 
stopping?" 

"What  do  you  mean?" 

"Why,  where  are  you  stopping? — what  hotel?" 

"I  don't  need  to  stop  at  a  hotel  I  have  a  home,  wife,  and 
children — why  should  I  go  to  a  hotel?" 

"Well,  now,  where  are  you?" 

"I'm  in  Mr.  Wallack's  office." 

"At  Indianapolis?" 

"Yes." 

"Thunder  you  are." 

"Yes;  I  was  talking  to  Charlie  Wilson,  and  got  him  to  connect 
you  without  posting  you. " 

"That's  good  enough.  Why,  I  get  you  splendidly;  No  trouble 
at  all" 

Mr.  Firman  and  Mr.  Smith  then  talked  quite  a  while  about 
instruments,  batteries,  and  such  things.  The  conversation  with 
Mr.  Firman  concluded  with  a  description  of  a  novel  business 
meeting : 

"Firman,  I  want  you  to  tell  a  gentleman  here,  who  is  listening, 
about  that  Director's  meeting  you  told  me  of  the  last  time  I  saw 
you." 

"Certainly.  We  had  a  Director's  meeting  of  our  Company. 
At  the  hour  appointed  we  lacked  three  of  a  quorum.  Of  course, 
they  all  have  telephone  wires  to  their  houses,  by  means  of  which 
we  learned  they  could  not  be  present.  It  was  suggested,  and 
carried  out,  that  the  meeting  be  held  by  telephone.  The  wires 
were  connected  so  all  could  hear  anything  said.  The  gentle- 
man who  had  prepared  the  resolution  we  wanted  to  consider 
read  it  from  his  house;  the  President  asked  each  how  he  should 
vote,  and  receiving  their  replies  declared  the  resolution  adopted, 
and  ordered  the  Secretary  to  record  it.  Several  lawyers  who 
have  heard  of  it  gave  it  as  their  opinion  that  the  meeting  was  a 


AND  HIS  INVENTIONS.  115 

legal  one.     If  that's  all,  I  will  ask  to  be  excused;  my  wife  wants 
to  go  to  church. " 

"All  right;  remember  us  in  your  prayers." 

"  Contract  is  too  large. " 

"You  can  go  now." 


Wonderful  Olfactory  Powers  of  the  Telephone  (?) 

When  the  telephone  line  connecting  the  water  works  at  the 
foot  of  Chicago  Avenue  with  the  new  water  works  at  Twenty- 
second  street  and  Ashland  Avenue  was  completed,  Mr.  Creiger, 
chief  engineer  of  the  Chicago  Avenue  establishment — who  by 
the  way  is  something  of  a  wag — desiring  to  test  the  new  tele- 
phone adjustment  called  up  the  institution  at  the  other  end  of 
the  line.  On  receiving  a  prompt  answer,  Mr.  Creiger  said: 

"Is  that  you,  John?" 

"Yes, "  said  John. 

C.     "How  do  you  feel  this  afternoon,  John?" 

J.     "Very  well,  I  thank  you." 

C.    "Been  eating  onions,  aint  you,  John?" 

J.  (Turning  round  to  an  operator  near  by  says  ):  "Thunder! 
I  knew  we  could  talk  through  this  thing,  but  I  didn't  know  before 
that  a  feller  could  smell  through  it !" 

As  a  matter  of  fact  John  had  eaten  heartily  of  onions  that  day 
for  dinner,  and  for  the  time  being  was  thoroughly  convinced  of 
this  new  attribute  of'  the  telephone. 


A  Canada  gentleman  stepped  into  a  friend's  office  in  Chicago, 
one  day,  just  in  time  to  hear  the  closing  words  of  a  telephone 
conversation  between  the  Chicago  man  and  another  party. 

"Oh,  Shut  up,"  says  the  Chicago  man,  "I  can  smell  your 
breath.  Don't  smoke  any  more  of  those  blamed  poor  cigars 
when  I  am  talking  to  you. " 

"Great  Caesar  1"  says  the  Canada  friend,  "You  can't  smell 
through  that  thing  can  you?" 

C  M.  "Oh,  yes,  splendidly."    (C.  M.  who  had  been  smoking, 


ntf  THOMAS  A.  EDISON 

quietly  puffs  into  the  telephone,)  "If  you  don't  believe  k  jairt 
come  and  try  it  yourself 

C.  F.  (Stepping  up  to  the  telephone)  "Halloo." 

"Halloo,"  (By  distant  party.) 

C.  F.  (Applies  nasal  organ)  "ni  declare  I  you  can  smell  hit 
breath,  can't  you?  I  wouldn't  have  believed  it." 


Burdette  and  Edison  Testing  the  Spanktrophone  1 

Burdette,  of  the  Burlington  Hawktye,  perpetrates  the  fol- 
lowing in  the  interest  of  "transmission  of  sound(?)M 

We  remember  meeting  Mr.  Edison,  some  years  ago,  when  he 
was  most  deeply  absorbed  in  his  experiments  relating  to  the  con- 
ductibility  of  sound  through  the  various  mediums,  and  had  a 
long  and  interesting  conversation  with  him  upon  that  subject. — 
We  conversed  upon  the  well-known  fact  that  the  same  medium 
of  transmission  has  different  properties  at  different  times.  We 
both  cited  instances  in  which  a  man  forty-three  years  old,  though 
using  his  utmost  strength  of  lung  and  voice,  could  not  shout 
loud  enough,  at  6 130  in  the  morning,  to  awaken  a  boy  nine  years 
old  just  on  the  other  side  of  a  lath  and  plaster  partition,  while 
at  1 1  o'clock  that  night  the  same  boy  would  hear  a  low  whistle 
on  the  sidewalk,  through  three  doors  and  two  flights  of  stairs, 
and  would  spring  instantly  out  of  a  sound  sleep  in  response  to 
it.  It  was  a  belief  of  Mr.  Edison's  at  that  time,  that  sound 
could  be  made  to  travel  as  rapidly  as  feeling,  and  to  test  the 
matter  he  had  invented  a  delicate  machine  called  the  spank- 
trophone,  which  he  was  just  about  trying  when  we  met  him. — 
We  were  greatly  interested  in  the  machine  and  readily  agreed 
to  assist  in  the  experiment.  By  the  aid  of  Mr.  Edison  and  a 
street-car  nickel,  we  enticed  into  the  laboratory  a  boy  about  7 
years  old.  After  many  times  reassuring  him  and  promising  him 
solemnly  that  he  would  not  be  hurt,  we  got  the  machine  attached 
to  him,  and  the  great  inventor  laid  the  boy  across  his  knees  hi 
the  most  approved  old-fashioned  Solomonic  method.  On  a  disc 


AND  HIS  INVENTIONS.  117 

of  the  machine  delicate  indices  were  to  record,  one  the  exact 
time  of  the  sound  of  the  spank,  the  other  the  exact  second  the 
boy  howled.  The  boy  was  a  little  suspicious  at  this  point  of  the 
experiment,  and  with  his  head  partly  turned,  was  glaring  fear- 
fully at  the  inventor.  Mr.  Edison  raised  his  hand.  A  piercing 
hoto!  rent  the  air,  followed  by  a  sharp  concussion  like  the  snap- 
ping of  a  musket  cap,  and  when  we  examined  the  dial  plate  of  the 
machine,  infallible  science  proudly  demonstrated  that  the  boy 
howled  sixty-eight  seconds  before  he  was  slapped.  The  boy  went 
down  stairs  in  three  strides,  with  an  injured  look  upon  his  fearful 
face.  Mr.  Edison  threw  the  machine  out  of  the  window  after 
the  urchin,  and  we  felt  that  it  was  no  time  to  intrude  upon  the 
sorrows  of  a  great  soul,  writhing  under  a  humiliating  sense  of  fail- 
ure. We  have  never  met  Mr.  Edison  since,  but  we  have  always 
thought  he  didn't  know  much  about  boys,  or  he  would  know  how 
utterly  unreliable  the  best  of  them  would  be  for  a  scientific 
experiment 


Eli  Perkins  and  Mr.   Edison. 

In  the  course  of  human  events,  Eli  Perkins  would  naturally 
meet  with  Mr.  Edison.  On  one  occasion,  according  to  E.  P.'s 
version,  the  interview  was  as  follows : 

It  pains  me  to  hear  of  so  many  people  being  burned  on 
account  of  elevators,  and  defective  flues.  To-day  Prof.  Edison 
and  I  laid  a  plan  before  the  Fire  Inspectors  which,  if  carried 
out,  will  remedy  the  evil. 

When  I  called  on  Prof.  Edison  at  Menlo  Park,  he  was  engaged 
on  a  new  experiment.     He  was  trying  to  abstract  the  heat  from 
the  fire,  so  as  to  leave  the  fire  perfectly  harmless,  while  the  heat 
could  be  carried   away  in  flour-barrels   to  be  used   for  cooking. 
Then  the  professor  tried  experiments   in  concentrating   water 
to  be  used  in  the  engines  in  case  of  drought.     The  latter  exper- 
iment proved  eminently  successful.     Twelve   barrels  of 
water  were  boiled  over  the  stove,  and  evaporated  down  to 
and  this   was  sealed  in  a  small  phial,    to  be  diluted  and 


n8  THOMAS  A.  EDISON 

to  put  out  fires  in  cases  of  drought,  or  in  cases  where  no  Croton 
water  can  be  had.  In  some  cases  the  water  was  evaporated 
and  concentrated  till  it  became  a  fine  dry  powder.  This  fine, 
dry  powder,  ths  Professor  tells  me,  can  be  carried  around  in  the 
pockets  of  the  firemen,  and  be  blown  upon  the  fires  through  tin 
horns, — that  is,  it  is  to  extinguish  the  fire  in  a  horn. 

I  examined  the  Professor's  pulverized  water  with  great  interest, 
took  a  horn — in  my  hands — and  proceeded  to  elucidate  to  him 
my  plan  for  constructing  fire-proof  flues.  I  told  him  that,  to 
make  fire-proof  flues,  the  holes  of  the  flues  should  be  con- 
structed of  solid  cast-iron,  or  some  other  non-combustible  mate- 
rial, and  then  cold  corrugated  iron,  without  any  apertures,  should 
be  poured  around  them. 

"Wonderful!"  exclaimed  Prof.  Edison  in  a  breath;  "but  where 
will  you  place  those  flues,  Mr.  Perkins?" 

"My  idea,"  I  replied,  drawing  a  diagram  on  the  wall-paper  with 
a  piece  of  charcoal,  "is  to  have  these  flues  in  every  instance 
located  in  the  adjoining  house." 

*  Magnificent  1  but  how  about  the  elevator?"  asked  the  Pro- 
fessor. 

"Why,  after  putting  them  in  the  next  house,  too,  I'd  seal  them 
up  water-tight,  and  fill  them  with  Croton,  and  then  let  them 
freeze.  Then  I'd  turn  them  bottom  side  up,  and,  if  they  catch 
fire,  the  flames  will  only  draw  down  into  the  cellar. " 

Prof.  Edison  said  he  thought,  my  invention  would  eventually 
supersede  the  telephone  and  do  away  entirely  with  the  necessity 
of  the  Keely  motor  M 


Satisfactory  Evidence. 

One  day,  just  before  a  thunder-storm,  a  man  stepped  into  a 
telegraph  office  and  requested  the  privilege  of  talking  through 
the  telephone  with  his  wife,  who  was  visiting  the  Manager's  wife 
at  a  distant  telegraph  station.  The  Assistant  manager  granted 
the  request,  and  the  man  began  operations.  He  couldn't  be 


AND  HIS  INVENTIONS.  119 

prevailed  upon  to  believe  that  it  was  really  his  wife  who  was 
talking  to  him,  and  she  so  many  miles  away.  He  finally  asked 
her  to  say  or  do  something  known  to  themselves  only,  that  he 
might  be  convinced  that  it  was  she.  Just  then  a  rambling  streak 
of  lightning  came  on  the  wires,  hitting  the  husband  on  the  head, 
when  he  jumped  to  his  feet  and  exclaimed:  "Oh-o-oh  dear! — 
I  am  satisfied;  all  correct;  It's  her!" 


Dawdles  Tries  the  Telephone. 

Mr.  Bassingbal,  city  merchant,  enjoys  the  luxury  of  a  private 
wire.  He  was  ecstatic  over  his  wonderful  telephone  and  in 
describing  it  to  a  special  friend  one  day  said : 

"Oh,  it's  magnificent;  very  convenient!  I  can  converse  with 
Mrs.  B.  just  as  if  I  was  in  my  own  drawing  room.  Stop;  I'll 
tell  her  you  are  here.  (Speaks  through  the  telephone.) 

"Dawdles  is  here — just  come  from  Paris — looking  so  well — de- 
sires to  be,"  etc.,  etc.  "Now  take  the  receiver,  Mr.  D.,  and 
you'll  hear  her  voice  distinctly" 

Dawdles.  "Weally!"  (Dawdles  takes  it  and  adjusts  to  his 
ear.) 

The  voice.  "  For  goodness  sake,  don't  bring  that  insufferable 
noodle  home  to  dine!" 


The  Telephone  and  the  Doctors. 

A  novel  use  of  the  Telephone  is  shown  in  the  following 
instance,  related  by  a  physician  of  Chicago. 

"I  attended  a  family  on  the  North  Side  near  Lincoln  Park. 
The  other  evening  about  1 1  p.  m.  they  'called'  me  through  the 
telephone,  saying:  "Our  baby  is  taken  suddenly  ill, — we  fear 
croup,  —  can  you  prescribe  without  coming  over?'  I  said 
'We  will  see.'  Has  the  child  fever?  What  is  its  temperature? 
In  a  few  moments  came  the  answer,  'Temperature  103, — skin 
hot  and  dry.'  (They  have  a  clinical  thermometer.)  'Is  the 


120  THOMAS  A.  EDISOflt 

breathing  quick?'  'No,  but  it  is  labored.  He  coughs  all  the 
time.  'Bring  the  child  as  near  as  possible  to  the  'receiver,'  and 
let  me  hear  him  cough.  In  a  moment  there  came  with  startling 
distinctness  to  my  ear  the  shrill,  crowing,  unmistakable  cough  as 
characteristic  of  croup !  I  directed  them  to  hold  the  child  there 
till  he  cried.  In  a  minute  or  two  I  heard  the  cry, — not  natural, 
but  hoarse,  still  further  verifying  my  diagnosis.  Knowing  that 
they  possessed  a  chest  of  medicines,  I  directed  them  to  give 
aconite  and  sanguinaria  in  rapid  alternation,  and  make  certain 
applications  to  the  throat.  The  answer  came,  'we  have  aconite, 
but  no  sanguinaria.' 

"Well,  Doctor,  what  could  you  do  in  such  a  dilemma? 

"Fortunately  there  is  a  druggist  within  a  few  blocks,  who  on 
inquiry  at  the  central  office,  I  ascertained  possesses  a  telephone. 
It  was  not  the  work  of  five  minutes  to  call  him  up,  and  direct 
him  to  send  to  No.  —  on  X  street  a  prescription  containing  the 
required  sanguinaria.  It  was  put  up,  delivered,  and  administered 
inside  of  half  an  hour,  and  the  whole  transaction,  consultation 
and  all,  did  not  extend  over  that  time. 

The  wonderful  fidelity  with  which  the  telephone  transmits  the 
peculiarities  of  the  human  voice  and  all  other  sounds  is  mar- 
velous. I  can  distinguish  the  laugh  of  each  member  of  a  family, 
and  even  any  variation  from  the  natural  voice  of  those  with 
whom  I  am  acquainted.  Also  the  nasal  voice  which  accompanies 
catarrh,  as  any  variety  of  cough. 

"The  telephone  of  the  future  will  enable  us  to  recognize  condi- 
tions of  morbid  states  in  patients  who  are  miles  away,  as  well  as 
if  they  were  sitting  in  our  offices.  With  a  microphone  attach- 
ment, we  may  be  able  to  hear  the  beating  of  the  heart,  and  any 
of  its  abnormal  sounds,  and  possibly,  to  record  the  tracings  of 
the  pulse,  to  hear  abnormal  sounds  occurring  during  respiration, 
and  perhaps  count  the  number  of  respirations  per  minute. 


AND  HIS  IN*£NTIO&    .  121 

The  Telephonograph. 

COMBINATION  OF  THE  TELEPHONE  AND  PHONOGRAPH. 

Mr.  Edison  has  devised  a  new  instrument  ;hat  combines  the 
telepone  and  phonograph,  which  he  calls  the  Teleponograph. 
It  is  a  simple  combination  of  the  two  instruments  as  shown  in 
the  accompanying  diagram.  The  drum  of  the  phonograph  is 
shown  in  section.  The  diaphragm,  instead  of  being  vibrated  by 


The  Telephonograph. 

the  voice,  is  vibrated  by  the  currents  which  traverse  the  helix  H, 
and  which  originate  at  a  distant  station.  The  object  of  this  new 
instrument  is  to  obtain  a  record  of  what  is  said  at  the  distant 
office,  which  can  be  converted  into  sound  when  desired.  The 
instrument  gives  additional  significance  to  the  phonograph. 


Edison's  "Baby." 

Among  the  many  instruments  which  Mr.  Edison  has  con- 
structed, he  has  perhaps  been  more  enthusiastic  over  this 
than  all  others.  For  some  time  after  its  invention  it  was  -his 
custom  to  exhibit  this  with  great  pride.  On  one  occasion  when 
showing  a  company  of  friends  through  the  Labratory  at  Menlo 
Park,  he  remarked  as  they  came  to  the  Phonogragh:  "I  have 
invented  a  great  many  machines,  but  this, "  said  he,  (patting  the 
phonograph)  is  my  baby,  and  I  expect  it  to  grow  up  and  be  a 
big  fellow  and  support  me  in  my  old  age.  * 


x>2  THOMAS  A.  EDISON 

The  Megaphone. 

This  is  among  Mr.  Edison's  latest  discoveries,  and  has  a  curi- 
ous origin.  "Strange  as  it  may  seem,"  says  Mr.  Edison,  "it  came 
to  life  through  the  mistake  of  a  reporter. "  To  use  his  own  words, 
"a  reporter  came  to  see  my  phonograph  and  went  back  and 
got  it  mixed  up  in  his  paper.  He  stated  that  I  had  got  up  a  ma- 
chine to  make  partially  deaf  people  hear.  The  item  was  exten- 
sively copied,  but  I  thought  nothing  more  of  it  until  after  a  while 
I  found  myself  receiving  letters  from  all  over  the  country  asking 
about  it  I  answered  some,  saying  it  was  a  mistake,  but  they 
kept  piling  in  upon  me  until  I  was  getting  them  at  the  rate  of 
twenty  and  thirty  a  day.  Then  I  began  thinking  about  the  mat- 
ter and  began  experimenting.  One  day  while  at  work  on  it  I 
heard  some  one  loudly  singing  '  Mary  Had  a  Little  Lamb.'  I 
looked  around,  nobody  was  near  me  and  nobody  was  singing. — 
Then  I  discovered  that  the  singer  was  one  of  my  young  men, 
who,  in  a  distant  corner  of  the  room,  was  softly  singing  to  him- 
self. The  instrument  had  magnified  the  sound,  and  I  heard  it 
distinctly,  although  I'm  pretty  deaf,  while  others  in  the  room  had 
not  heard  a  whisper.  That  was  the  first  of  the  megaphone. " 

No  electricity  is  used  in  this  instrument.  It  is  a  peculiarly 
constructed  ear  trumpet.  For  use  in  the  open  air  it  is  made 
very  large  and  consists  of  two  great  ear-trumpets  and  a  speaking 
trumpet;  mounted  together  upon  a  tripod.  Two  persons  pro- 
vided with  this  instrument  are  enabled  to  converse  in  the  ordina- 
ry tones  of  voice  some  miles  apart 

A  smaller  instrument  is  made  for  deaf  persons,  which  is  porta- 
ble and  adjustable,  similar  to  an  opera  glass,  by  means  of  which 
a  whisper  is  heard  through  the  largest  hall  While  on  a  recent 
visit  to  Chicago,  Mr.  Edison,  in  view  of  his  own  deafness,  face- 
tiously remarked  to  a  friend  that  he  ought  to  have  had  one  of 
these  instruments  with  him,  and  in  the  same  strain  described  the 
trumpet  as  one  that  was  unnecessary  to  "bawl  into!" 

Mr.  Edison  is  now  improving  the  megaphone,  and  states  that 
he  will  use  electricity  in  its  construction  which  will  require  a 
small  battery.  It  will  doubtless  prove  a  blessing  to  deaf  persons. 


AND  HIS  INVENTIONS.  123 

The  Sonorous  Voltameter. 

This  high-sounding-titled  instrument  is  amusingly  described  by 
Mr.  Edison,  to  a  friend,  as  follows : 

"Have  you  seen  the  Sonorous  Voltameter  yet?"  said  Mr.  E.  to 
his  friend. 

The  friend  admitted  that  the  sonorus  voltameter  was  as  yet 
outside  the  pale  of  his  scientific  education,  and  asked  for  light  on 
the  subject. 

Mr.  Edison  doffed  his  hat;  and  by  a  dexterous  throw  landed 
it  on  a  table  several  feet  away.  Then  he  took  paper  and  pencil 
and  drew  a  sonorous  voltameter. 

"There  she  is,"  he  exclaimed,  joyfully,  as  he  put  on  the  fin- 
ishing touches  to  a  complex  arrangement  of  wires,  batteries, 
tubes,  and  funnels. 

"What  is  she  good  for, "  inquired  the  friend,  adopting  the  in- 
ventor's metaphor  and  gazing  on  the  unintelligible  combination. 

"First-class  arrangement.  Tells  of  the  strength  of  telegraph 
batteries  right  to  a  dot.  It  makes  you  hear  their  strength.  This 
end  of  the  wire,  you  see,  makes  the  oxygen,  and  this  end  hydro- 
gen. The  bubbles  rise  and  make  a  noise,  which  is  magnified  by 
the  funnel.  These  glass  tubes  indicate  the  intensity  of  the  current 
by  degrees,  and  the  funnel  indicates  the  same  by  sound.  You 
take  your  watch  and  count  the  number  of  ticks  caused  by  the 
bubbles  per  second.  Thus  you  know  how  strong  your  battery 
is.  Just  try  it  some  time. 

The  astonished  companion  promised  that  the  first  time  he 
found  a  battery  lying  around  without  any  owner  he  would  clap 
on  a  sonorous  voltameter  and  find  out  all  about  it. 


Edison  Joking  his  Friends. 

Mr.  Edison  is  fond  of  joking  with  his  intimate  friends.  In  the 
presence  of  a  company  of  these  one  day  at  Melno  Park,  and 
just  as  they  were  drawing  on  their  great  coats  preparatory  to  de- 


i*4  THOMAS  A.  EDISON 

parture,  Mr.  Edison  astounded  the  party  by  gravely  announcing 
as  follows : 

"Gentlemen,  I  am  now  about  to  tell  you  something  that  will 
astonish  all  the  electricians  in  the  world.  I  am  prepared  to  send 
a  current  of  electricity  from  here  to  Philadelphia  without  any 
wire. 

Down  came  the  great  coats  in  a  hurry. 

"Why  Al,  (his  second  name  is  Alva,  and  many  of  his  friend? 
call  him  Al,)  that's  impossible, "  said  a  friend,  who  was  an  old 
telegraph  operator. 

"Oh,  no,"  answered  Mr.  Edison.  "It  can  be  done,  and  I 
know  it  It  is  the  result  of  a  recent  discovery. " 

"  How, "  inquired  several  at  once. 

"Store  it  up  in  a  condenser  and  send  it  there  by  express,"  was 
the  reply.  "Now  don't  give  it  away  to  the  newspaper  men." 

Ha,  Ha,   Ho,  Ho,  just  so,    you're  right,  said  his  friend. 


Down  in  the   Gold   Mines. 

During  his  trip  to  the  Rocky  Mountains  Mr.  Edison  visited  a 
number  of  the  gold  mines.  It  was  soon  reported  that  he  had 
discovered  a  method  of  finding  gold  without  digging  for  it. — 
Tins,  he  pronounced  a  misstatement,  and  says: 

What  I  did  get  up  was  a  simple  contrivance  for  ascertaining 
the  quantity  of  ore  in  any  given  place  once  gold  is  struck.  It  is 
a  very  simple  thing  and  absolutely  reliable. 

"The  ore  is  surrounded  by  a  bed  or  bank  of  conducting  ma- 
terial. For  instance,  in  the  mines  which  I  examined  that 
material  was  clay.  The  quantity  of  clay  is  an  indication  of  the 
quantity  of  ore.  When  ore  is  struck  thousands  are  often  ex- 
pended in  drilling  for  more,  when  in  reality  the  vein  is  completely 
exhausted.  The  contrivance  I  suggested  enables  the  miner  to 
know  whether  or  not  the  vein  is  exhausted.  I  simply  make 
a  ground  connection  and  run  a  wire  through  a  battery  and  in- 
strument Now,  I  take  the  other  end  of  the  wire  down  the 


AND  HIS  INVENTIONS.  1*5 

shaft  and  connect  it  with  the  clay  or  other  conducting  material 
surrounding  the  ore.  If  the  clay  bank  is  extensive  the  connec- 
tion is  a  good  one,  and  the  current  of  electricity  flows  freely; — 
but  if  the  clay  bank  is  small  in  area  a  poor  connection  is  formed. 
By  adopting  a  unit  of  measurement  the  area  can  be  told  almost 
to  the  square  foot 


Edison's  Anecdote  of  the  Rocky  Mountain  Scouts. 

Mr.  Edison  made  an  extensive  trip  to  the  Mocky  Mountains 
in  July,  1878,  to  test  his  tasimeter  on  the  sun's  corona  during  a 
total  eclipse  of  that  luminary.  While  there,  he  went  off  buf- 
falo hunting,  which  gave  occurrence  to  the  following  little  story, 
in  the  presence  of  a  few  friends,  after  his  return  to  Menlo  Park : 

"That  Western  country  is  a  great  country, "  his  face  beaming 
as  he  thought  of  his  recent  vacation.  "Those  scouts  out  there 
are  wonderful  fellows.  One  of  them  tracked  us  on  one  occasion 
over  a  distance  of  eighty  miles,  and  all  that  he  had  to  guide  him 
was  tobacco  juice. " 

"Tobacco  juice!  How  in  the  world  could  tobacco  juice 
guide  a  man?"  asked  one  of  his  friends. 

"It  happened  in  this  way.  A  cable  dispatch  came  for  me  at 
Rawlins,  but  I  had  gone  out  hunting  with  a  party  of  thirteen, 
some  of  whom  were  old  Western  hunters.  Word  was  cabled 
back  that  the  message  could  not  be  delivered,  as  our  whereabouts 
were  unknown.  Soon  an  answer  came  to  send  out  a  scout  in 
search  of  us.  The  scout  traveled  for  three  days  over  the  wildest 
sort  of  country,  with  nothing  to  guide  him  but  tobacco  juice, 
which  the  hunters  of  our  party,  who  were  inveterate  chewers,  left 
behind.  Once  he  lost  the  trail  and  was  for  hours  in  doubt,  but 
he  again  got  it.  Sharp  fellows,  those  scouts." 


i26  THOMAS  A.  EDISON- 


The  Tasimeter  or  Thermopile. 

AN  INSTRUMENT  THAT  MEASURES  THE  HEAT  OF  THE  STARS — How  IT  is 
DONE — FULL  ACCOUNT  OF  ITS  DISCOVERY. 

This  is  a  new  invention  by  Mr.  Edison  for  measuring  to  an 
astonishing  exactness  a  very  low  degree  of  heat  It  is  so  sen- 
sitive in  its  operating  facilities  that  it  registers  the  heat  from  the 
fixed  stars  and  will  no  doubt,  from  this  fact,  prove  a  great  ad- 
junct in  the  science  of  astronomy.  It  also  registers  with  equal 
precision  the  presence  of  moisture.  It  ranks  among  the  most 
wonderful  of  Mr.  Edison's  many  inventions  and  is  described  in 
his  own  language  as  follows: 

"It  consists  of  a  carbon  button  placed  between  two  metalic 
plates.  A  current  of  electricity  is  passed  through  one  plate, 
then  through  the  carbon,  and  through  the  other  plate.  A  piece 
of  hard  rubber  or  of  gelatine  is  so  supported  as  to  press  against 
these  plates.  The  whole  is  then  placed  in  connection  with  a  gal- 
vanometer and  an  electric  battery.  Heat  causes  the  strip  of  hard 
rubber  to  expand  and  press  the  plates  closer  together  on  the 
carbon,  allows  more  current  to  pass  through,  and  deflects  the 
needle  of  the  galvanometer.  Cold  decreases  the  pressure. — 
Moisture  near  the  strip  of  the  gelatine  can  be  measured  in  the 
same  way  by  increasing  or  decreasing  the  pressure  and  accord- 
ingly deflecting  the  needle.  By  means  of  this  apparatus  or  one 
combined  with  sensitive  electrical  galvanometers  it  is  possible  to 
measure  the  millionth  part  of  a  degree  Fahrenheit.  Infinitesi- 
imal  changes  in  the  moisture  of  the  atmosphere  can  be  indicated 
in  the  same  way, — changes  which  are  a  hundred  thousand  times 
less  in  quantity  than  those  that  can  be  indicated  by  the  present 
barometer.  It  will  thus  foretell  a  storm  much  more  readily. — 
The  carbon  button  I  have  in  this  instrument  is  of  lampblack 
burned  from  rigolene.  I  discovered  about  two  years  ago  that 
carbon  of  various  forms,  such  as  plumbago,  graphite,  gas  retort 
carbon,  and  lampblack,  when  molded  in  buttons,  decreased  the 
resistance  to  the  passage  of  the  electrical  current  by  pressure. 


AND  HIS  INVENTIONS.  127 

This  is  part  of  the  apparatus  of  the  carbon  telephone  and  micro- 
phone. 

The  Tasimeter  was  discovered  by  Mr.  Edison  in  the  following 
manner :  During  his  investigations,  which  resulted  in  the  inven- 
tion of  his  carbon  telephone,  Mr.  Edison  found  that  carbon  was 
subject  to  expansion  and  contraction  under  conditions  of  elec- 
tric influence  and  pressure  that  made  it  the  most  sensitive  sub- 
stance within  reach  of  the  scientist.  Applying  this  discovery 
to  the  measurement  of  heat,  he  found  that  by  using  even  an  or- 
dinary electronemer,  the  pressure  on  the  carbon  disk  caused  by 
the  expansion  of  any  substance  acted  on  by  even  the  lowest 
degree  of  heat  reacted  so  as  to  govern  the  movements  of  the 
balanced  needle  over  a  finely  graduated  scale.  This  invention 
he  has  been  long  engaged  in  perfecting.  He  was  invited  by 
Prof.  Langley,  of  Pittsburg,  to  adapt  it  for  measuring  the  heat  of 
stellar  spectra.  This  he  has  succeeded  in  accomplishing,  with 
such  wonderful  success  that  he  is  now  able  to  measure  the  heat 
of  even  the  telescopic  stars.  By  focussing  the  heat  rays  of  these 
distant  bodies  so  as  to  concentrate  them  on  the  substance  press- 
ing on  the  carbon  button,  he  is  enabled  to  measure  accurately 
their  relative  and  actual  heats.  In  this  way  it  is  not  improbable 
astronomical  researches  as  to  the  distance  of  the  stars  from  the 
earth,  may  be  measured  by  their  degrees  of  heat  acting  on  the 
thermopile.  The  condition  of  moisture  can  also  be  determined 
by  its  effect  on  a  bar  of  gelatine  substituted  for  the  hard  rubber 
used  for  measuring  heat.  Indeed  so  sensitive  to  the  influence  of 
moisture  is  this  delicate  instrument,  that  a  little  water  spilled  on 
the  ground  in  the  same  room  with  the  instrument,  or  even,  as 
Mr.  Edison  asserts,  spitting  on  the  floor  will  be  indicated  by  the 
the  movement  of  the  the  balanced-needle. 


128  THOMAS  A.  EDISON 

The  Tasimeter  and  the  Stars. 

EXPLANATION — TEST — THE  HEAT  OF  ARCTURUS  REGISTERED. 

The  value  of  the  tasimeter  lies  in  its  ability  to  detect  the 
smallest  variation  in  temperature.  This  is  accomplished  indi- 
rectly. The  change  of  temperature  causes  expansion  or  con- 
traction of  a  rod  of  vulcanite,  which  changes  the  resistance 
of  an  electric  circuit  by  varying  the  pressure  it  exerts  upon  a 
carbon-button  included  in  the  circuit.'  During  the  eclipse  of 
July  29,  1878,  it  was  thoroughly  tested  by  Mr.  Edison,  and  dern- 
demonstrated  the  existence  of  heat  in  the  corona. 


The  Tasimeter. 

The  instrument,  as  used  on  that  occasion  by  Mr.  Edison  is 
shown  in  section  in  the  engraving,  which  affoids  an  insight  into 
its  construction  and  mode  of  operation.  The  subtance  where 
expansion  is  to  be  measured  is  shown  at  A.  It  is  firmly  clamped 
at  B,  its  lower  end  fitting  into  a  slot  in  the  metal  plate  M,  which 
rests  upon  the  carbon-button,  C.  The  latter  is  in  an  electric 
circuit,  which  includes  a  delicate  galvanometer.  Any  variation 
in  the  length  of  the  rod  changes  the  pressure  upon  the  carbon, 
and  alters  the  resistance  of  the  circuit.  This  causes  a  deflec- 
tion of  the  galvanometer-needle — a  movement  in  one  direction 


AND  HIS  INVENTIONS.  129 

denoting  expansion  of  A,  while  an  opposite  motion  signifies  con- 
traction. To  avoid  any  deflection  which  might  arise  from  change 
in  strength  of  battery,  the  tasimeter  is  inserted  in  an  arm  of  the 
Wheatstone  bridge. 

In  order  to  ascertain  the  exact  amount  of  expansion  in  deci- 
mals of  an  inch,  the  screw,  S,  seen  in  front  of  the  dial,  is  turned 
until  the  deflection  previoucly  caused  by  the  change  of  tempera- 
ture is  reproduced.  This  screw  works  a  second  screw,  causing 
the  rod  to  ascend  or  descend,  and  the  exact  distance  through 
which  the  rod  moves  is  indicated  by  the  needle,  N,  on  the  dial. 

This  novel  instrument  was  completed  only  two  days  before 
Mr.  Edison  went  West  in  July,  1878,  to  experiment  on  the  sun's 
corona.  It  was  set  up  immediately  on  his  arrival  at  Rawlins, 
but  he  found  great  difficulty  in  fully  adjusting  so  delicate  an  in- 
strument. This,  he  however,  finally  effected  by  new  and  ingen- 
ious devices,  which  he  designates  "fractional  balancing."  In 
order  to  form  some  idea  of  the  delicacy  of  the  apparatus  when 
thus  adjusted  to  measure  the  smallest  amount  of  heat,  "the  tasi- 
meter," says  Mr.  Edison,  "being  attached  to  the  telescope,  the 
image  of  the  star  Arcturus  was  brought  on  the  vulcanized  rubber. 
The  spot  of  light  from  the  galvanometer  moved  to  the  side  of 
heatr 

After  some  minor  adjustments,  five  uniform  and  successful  de. 
flections  were  obtained  with  the  instrument,  as  the  light  of  the 
star  was  allowed  to  fall  on  the  vulcanite  to  produce  the  deflec- 
tion, or  was  screened  off  to  allow  of  a  return  to  zero. "  The 
tasimeter  on  this  occasion  was  placed  in  a  double  tin  case,  with 
water  at  the  temperature  of  the  air  between  each  case.  This 
case  was  secured  to  a  Dollond  telescope  of  four  inches  aperture. 


Testing  the  Tasimeter  on  the  Sun's  Corona. 

This  wonderful  invention  was  tested  by  Mr.  Edison  at  Raw- 
lins, Wyoming  Territory,    on  the  sun's  corona  during  the  total 
eclipse  of  July  29th.  1878.     Though  attended  with  much  labor 
9 


*3°  THOMAS  A.  EDISON 

and  difficulties  the  demonstration  was  successful  A  graphic 
description  of  the  first  great  trial  of  the  tasimeter  appeared  at 
the  time  in  a  New  York  journal,  from  which  we  give  the  fol- 
lowing extract : 

But  a  new  evil  soon  became  manifest.  A  strong  wind  began 
blowing  the  frail  pine  structures  used  for  observatories.  These 
commenced  to  rock.  Edison's  observatory,  which,  in  its  normal 
condition,  is  a  hen-house,  was  particularly  susceptible.  He 
hurried  toward  it  only  to  find  his  sensitively-adjusted  apparatus 
in  an  extreme  state  of  commotion.  Every  vibration  threw  the 
tasimeter  into  a  new  condition  of  adjustment  To  remedy  the 
evil  was  far  from  easy,  as  the  time  was  then  so  short  and  precious 
it  was  too  late  to  remove  the  apparatus,  and  seemingly  impossi- 
ble to  break  the  force  of  the  wind,  which  was  gradually  increas- 
into  a  tornado.  Hatless  and  coatless  he  ran  to  a  neighboring 
lumber-yard,  and  in  a  moment  a  dozen  stalwart  men  were  car- 
rying boards  with  which  to  prop  up  the  structure  and  erect  a 
temporary  fence  at  its  side.  This  completed,  the  chronometer 
indicated  half-past  one  o'clock. 

At  thirteen  minutes  past  2  the  moon  began  to  make  her  first 
appearance  between  the  sun  and  earth.  Again  Edison  adjusted 
his  tasimeter,  but  only  to  find  that  the  gale  continued  to  sway 
his  projecting  telescope  so  violently  that  a  satisfactory  result  was 
almost  impossible.  A  rigging  of  wire  and  ropes  soon  partially 
overcame  the  difficulty,  and  once  more  the  instruments  were 
ready  for  work.  In  a  few  moments  there  came  Dr.  Draper  and 
the  announcement,  "There  she  goes,"  and  the  crowd  of  specta- 
tors immediately  leveled  their  smoked  glasses  at  the  sun.  The 
moon  had  just  made  her  appearance. 

At  half-past  i  p.  m.  one  quarter  of  the  sun's  disc  was  darkened 
with  slow  but  steady  pace.  The  progress  of  the  moon  continued. 
In  the  observatory  of  Dr.  Draper  the  fall  of  a  pin  could  be 
heard;  outside  almost  equal  quiet  reigned.  The  only  place  of 
disorder  was  in  that  frail  structure  of  Edison's.  Notwithstand- 
ing his  efforts  the  wind  continued  to  give  him  trouble.  In  vain 
he  adjusted  and  readjusted.  At  3  o'clock  three-quarters  ot  the 


AND  HIS  INVENTIONS.  131 

sun's  disc  was  obscured,  and  darkness  began  to  fall  upon  the 
surrounding  region.  The  hills  around  were  all  alive  with  people 
watching  for  the  moment  of  totality.  In  Dr.  Draper's  observa- 
tory everything  was  proceeding  excellently.  The  force  of  the 
wind  had  been  broken.  Edison's  difficulty  seemed  to  increase 
as  the  precious  moments  of  total  eclipse  drew  near.  At  five 
minutes  past  3  o'clock,  the  sun's  disc  was  seven-eighths  covered, 
and  the  country  around  was  shrouded  in  a  pale  grayish  light, 
resembling  early  dawn. 

At  a  quarter  past  3  darkness  was  upon  the  face  of  the  earth. 
The  few  moments  for  which  the  astronomers  had  traveled  thou* 
sands  of  miles  had  arrived.  Still  Edison's  tasimeter  was  out  of 
adjustment.  All  the  other  instruments  were  in  excellent  working 
order.  Totality  had  brought  with  it  a  marked  cessation  in  the 
force  of  the  wind.  Edison  worked  assiduously,  but  the  tasimeter 
would  not  come  to  a  proper  condition.  At  last,  just  as  the 
chronometer  indicated  that  but  one  minute  remained  of  total 
eclipse,  he  succeeded  in  concentrating  the  light  from  the  corona 
upon  the  small  opening  of  the  instrument.  Instantly  the  fire  ray 
of  light  on  his  graduating  scale  swept  along  to  the  right,  clear- 
ing its  boundaries.  Edison  was  overjoyed.  The  experiment  has 
shown  the  existence  of  about  fifteen  times  more  heat  in  the 
corona  than  that  obtained  from  the  star  Arcturus  the  previous 
night. 

Edison's  tasimeter  showed  its  power  to  measure  the  corona's 
heat.  It,  however,  was  adjusted  ten  times  too  sensitively.  Never 
having  used  it  before  for  a  similar  purpose,  he  had  no  means  of 
telling  the  degree  of  sensitiveness  necessary.  The  heat  from 
the  corona  threw  the  ray  of  light  entirely  off  the  scale,  and  before 
he  could  make  the  second  test  the  eclipse  had  passed  away.  The 
experiment  demonstrated  that,  compared  to  some  of  the  fixed 
stars,  the  corona's  heat  was  much  greater. 


xj  2  THOMAS  A.  EDISON 

Basis  of  the  Tasimeter. 

The  tasimeter  is  a  modification  of  the  micro-tasimeter  which 
is  the  outcome  of  Mr.  Edison's  experiments  with  his  carbon 
telephone.  Having  experimented  with  diaphragms  of  various 
thicknesses,  he  ascertained  that  the  best  results  were  secured  by 
using  the  thicker  diaphragms.  At  this  stage  he  experienced  a 
new  difficulty.  So  sensitive  was  the  carbon  button  to  the 
changes  of  condition,  that  the  expansion  of  the  rubber  telephone 
handle  rendered  the  instrument  inarticulate,  and  finally  inopera- 
tive. Iron  handles  were  substituted  with  a  similar  result,  but 
with  the  additional  feature  of  musical  and  creaky  tones  distinct- 
ly audible  in  the  receiving  instrument.  These  sounds  Mr. 
Edison  attributes  to  the  movement  of  the  molecules  of  iron 
among  themselves  during  expansion.  He  calls  them  "molecular 
music."  To  avoid  these  disturbances  in  the  telephone,  the 
handle  was  dispensed  with;  but  it  had  done  a  great  ser- 
vice in  revealing  the  extreme  sensitiveness  of  the  carbon 
button,  and  this  discovery  opened  the  way  for  the  invention  of 
this  new  and  wonderful  instrument. 

The  micro-tasimeter  is  represented  in  perspective  in  fig,  12, 
in  section  in  fig.  13,  and  the  plan  upon  which  it  is  arranged  in 
the  electric  circuit  is  shown  in  fig.  14. 

The  instrument  consists  essentially  in  a  rigid  iron  frame  for 
holding  the  carbon  button,  which  is  placed  between  two  plati- 
num surfaces,  one  of  which  is  fired  and  the  other  moveable,  and 
in  a  device  for  holding  the  object  to  be  tested,  so  that  the  pres- 
sure resulting  from  the  expansion  of  the  object  acts  upon  the 
carbon  button. 

Two  stout  posts  A,  B,  project  from  the  rigid  base  piece,  c.  A 
vulcanite  disc  D,  is  secured  to  the  post  A,  by  the  platinum-headed 
screw  E,  the  head  of  which  rests  in  the  bottom  of  a  shallow 
circular  cavity  in  the  centre  of  the  disc.  In  this  cavity,  and  in 
contact  with  the  head  of  the  screw  E,  the  carbon  button  F,  is 
placed.  Upon  the  outer  face  of  the  button  there  is  a  disc  of 
platinum  foil,  which  is  in  electrical  communication  with  the 


AND  HIS  INVENTIONS.  133 

battery.  A  metalic  cup  G,  is  placed  in  contact  with  the  platinum 
disc  to  receive  one  end  of  the  strip  of  whatever  material  is  em- 
ployed to  operate  the  instrument. 

The  post  B,  is  about  four  inches  from  the  post  A,  and  contains 


Fig  13.  Fig.  14. 

a  screw-acted  follower  H,  that  carries  a  cup  i,  between  which 
and  the  cup  G,  is  placed  a  strip  of  any  substance  whose  expansi- 
bility it  is  desired  to  exhibit.  The  post  A,  is  in  electrical  com- 
munication with  a  galvanometer,  and  the  galvanometer  is 


xj4  THOMAS  A.  EDISON 

connected  with  the  battery.  The  strip  of  the  substance  to  be 
tested  is  put  under  a  small  initial  pressure,  which  deflects  the 
galvanometer  needle  a  few  degrees  from  the  needle  point.  When 
the  needle  comes  to  rest,  its  position  is  noted.  The  slightest 
subsequent  expansion  or  contraction  of  the  strip  will  be  indicated 
by  the  movement  of  the  galvanometer  needle.  A  thin  strip  of 
hard  rubber,  placed  in  the  instrument,  exhibits  extreme  sensi- 
tiveness, being  expanded  by  heat  from  the  hand,  so  as  to  move 
through  several  degrees  the  needle  of  a  very  ordinary  galvanom- 
eter, which  is  not  effected  in  the  slightest  degree  by  a  thermopile 
facing  and  near  a  red  hot  iron.  The  hand,  in  this  experiment, 
is  held  a  few  inches  from  the  rubber  strip.  A  strip  of  mica  is 
sensibly  affected  by  the  heat  of  the  hand,  and  a  strip  of  gelatin, 
placed  in  the  instrument,  is  instantly  expanded  by  moisture  from 
a  dampened  piece  of  paper  held  two  or  three  inches  away. 

For  these  experiments  the  instrument  is  arranged  as  in  fig.  1 2, 
but  for  more  delicate  operations  it  is  connected  with  a  Thom- 
son's reflecting  galvanometer,  and  the  current  is  regulated  by  a 
Wheatstone's  bridge  and  a  rheostat,  so  that  the  reistance  on 
both  sides  of  the  galvanometer  is  equal,  and  the  light-pencil 
from  the  reflector  falls  on  o°  of  the  scale.  The  principle 
of  this  arrangement  is  illustrated  by  the  diagram,  fig.  14.  Here 
the  galvanometer  is  at  g,  and  the  instrument  which  is  at  i,  is  ad- 
justed, say,  for  example,  to  ten  ohms  resistance.  At  a,  b,  and 
c,  the  resistance  is  the  same.  An  increase  or  diminution  of  the 
pressure  on  the  carbon  button  by  an  infinitesimal  expansion  or 
contraction  of  the  substance  under  test  is  indicated  on  the  scale 
of  the  galvanometer. 

The  carbon  button  may  be  compared  to  a  valve,  for,  when  it 
is  compressed  in  the  slightest  degree,  its  electrical  conductivity 
is  increased,  and  when  it  is  allowed  to  expand  it  partly  loses  its 
conducting  power. 

For  measuring  the  heat  of  the  stars,  etc.,  this  instrument  is 
slightly  modified  so  as  to  admit  the  light  or  heat  at  G,  to  the  car- 
bon button  F.  Mr.  Edison  proposes  to  apply  the  principle  of 
this  instrument  to  delicate  thermometers,  barometers,  hygrom- 
eters, etc.,  and  ultimately  to  weigh  the  light  of  the  sun. 


136  THOMAS  A.  EDISON 

Pressure   Relay. 

In  this  novel  and  useful  instrument  Mr.  Edison  takes  the  ad- 
7  ant  age  of  the  remarkable  property  which  plumbago  possesses 
of  decreasing  its  resistance  enormously  under  slight  pressure. 
Thin  discs  of  plumbago  are  placed  upon  the  cupped  poles  of  an 
electro-magnet — as  shown  in  Fig.  15;  p.  135 — the  coils  of  which 
have  several  hundred  ohms  resistance.  Upon  the  discs  of  plum- 
bago is  laid  the  armature  which  is  provided  with  a  binding  post 
for  clamping  the  local  battery  ware. 

The  core  of  the  magnet,  the  plumbago  discs,  and  the  arma- 
ture are  included  in  a  local  circuit,  which  also  contains  an  ordi- 
nary sounder  and  several  cells  of  bichromate  ba'tery.  The 
relay  magnet  is  inserted  in  the  main  line  in  the  usual  man- 
ner. The  operation  is  as  follows :  When  the  main  circuit  is 
opened  the  attraction  for  the  armature  ceases,  and  the  only  pres- 
sure upon  the  plumbago  discs  is  due  to  the  weight  of  the  arma- 
ture itself.  With  this  pressure  only  the  resistance  of  the  plumbago 
to  the  passage  of  the  local  current  amounts  to  several  hundred 
ohms;  with  this  resistance  in  the  local  circuit  the  sounder  remains 
open.  If  now  the  main  circuit  be  closed,  a  powerful  attraction 
is  set  up  between  the  poles  of  the  relay  magnet  and  its  armature, 
causing  a  great  increase  in  the  pressure  upon  the  plumbago  discs, 
and  reducing  its  resistance  from  several  hundred  to  several  ohms, 
consequently  the  sounder  closes.  So  far  the  result  differs  but 
little  from  the  ordinary  relay  and  sounder.  But  the  great  differ- 
ence between  this  relay  and  those  in  common  use,  and  its  value, 
rests  upon  the  fact  that  it  repeats  or  translates  from  one  circuit 
into  another,  the  relative  strengths  of  the  first  circuit.  For  in- 
stance, if  a  weak  current  circulates  upon  the  line  in  which  the 
relay  magnet  is  inserted,  the  attraction  for  its  armature  will  be 
small,  the  pressure  upon  the  plumbago  discs  will  be  light,  conse- 
quently a  weak  current  will  circulate  within  the  second  circuit; 
and  on  the  contrary,  if  the  current  in  the  first  circuit  be  strong, 
the  pressure  upon  the  plumbago  discs  will  be  increased,  and  in 
proportion  will  the  current  in  the  second  circuit  be  increased 


AND  HIS  INVENTIONS. 


137 


No  adjustment  is  ever  required.  It  is  probably  the  only  device 
yet  invented  which  will  allow  of  the  translation  of  signals  of 
variable  strengths,  from  one  circuit  into  another,  by  the  use  of 
batteries  in  the  ordinary  manner. — This  apparatus  was  designed 
by  Mr.  Edison  for  repeating  the  acoustical  vibrations  of  vari- 
able strengths  in  his  speaking  telegraph. 


Fig-  *5 «'  Pressure  Relay. 


ijg  THOMAS  A.  EDISON 

The  Carbon  Rheostat. 

A  NEW   AND   VALUABLE    INSTRUMENT — BALANCING   THE    ELECTRICAL 
CURRENT — How  IT  is  DONE. 

In  quadruplex  telegraphy  it  is  vital  to  the  working  of  the  sys- 
tem to  perfectly  balance  the  electrical  current. 

The  common  method  of  doing  this  is  to  employ  a  rheostat 
containing  a  great  length  of  resistance  wire,  more  or  less  of  which 
may  be  thrown  into  or  cut  out  of  the  electrical  circuit  by  in- 
serting or  withdrawing  plugs  or  keys.  This  operation  often 
requires  thirty  minutes  or  more  of  time  that  is  or  might  be  very 
valuable. 

To  remedy  this  difficulty  Mr.  Edison  has  devised  the  instru- 
ment represented  in  the  engraving,  Fig.  16  being  a  perspective 
view  and  Fig.  1 7  a  vertical  section. 

A  hollow  vulcanite  cylinder,  A,  is  screwed  on  a  boss  on  the 
brass  plate,  B.  Fifty  discs — cut  from  a  piece  of  silk  that  has 
been  saturated  with  sizing  and  well  filled  with  fine  plumbago  and 
dried — are  placed  upon  the  boss  of  the  plate,  B,  and  are  sur- 
mounted by  a  plate,  C,  having  a  central  conical  cavity  in  its 
upper  surface.  A  pointed  screw,  D,  passes  through  the  cap,  E, 
at  the  top  of  the  cylinder,  A,  and  projects  into  the  conical  cavity 
in  the  plate  C.  The  screw  is  provided  with  a  disc,  F,  having  a 
knife  edge  periphery,  which  extends  to  the  scale,  and  serves  as 
an  index  to  show  the  degree  of  compression  to  which  the  silk 
discs  are  subjected. 

The  instrument  is  placed  in  the  circuit  by  connecting  the  cap, 
E,  with  one  end  of  the  battery  wire  and  the  plate,  B,  with  the 
other  end. 

The  principle  of  the  instrument  is  identical  with  Mr.  Edison's 
carbon  telephone.  The  compression  of  the  series  of  discs  in- 
creases conductivity:  a  diminution  of  pressure  increases  the 
resistance.  Any  degree  of  resistance  within  the  scope  of  the  in- 
strument may  be  had  hy  turning  the  screw  one  way  or  the  other. 

In  this  instrument  the  resistance  may  be  varied  from  400  to 
6,000  ohms,  and  any  amount  of  resistance  may  be  had  by  in- 
creasing the  number  of  silk  discs. 


140 


THOMAS  A.  EDISON 
The  Aerophone. 


The  great  object  of  this  instrument  is  to  increase  the  loudness 
of  spoken  words,  without  impairing  the  distinctness  of  articula- 
tion. The  working  of  the  mechanism  is  as  follows : 

The  magnified  sound  proceeds  from  a  large  diaphragm,  which 


Fig.  18;  Aerophone,  (i.) 

is  vibrated  by  steam  or  condensed  air.  The  source  of  power  is 
controlled  by  the  motion  of  a  second  diaphragm,  vibrating  undev 
the  influence  of  the  sound  to  be  magnified.  There  are,  there 
fore,  three  distinct  parts  to  the  instrument :  First,  a  source  of 
power — steam  or  compressed  air;  second,  an  instrument  to 
control  the  power;  and  third,  a  diaphragm  vibrating  under  the 


Fig.  19;  Aerophone,  (2.) 

influence  of  the  power.  The  first  of  these  is  usually  compressed 
air,  supplied  from  a  tank.  It  is  necessary  that  it  should  be  of 
constant  pressure. 

The  second  is  shown  in  section  in  Fig.  18,  and  consists  of  a 
diaphragm  and  mouth-piece,  like  those   used  in   the  telephone. 


AND  HIS  INVENTIONS.  141 

A  hollow  cylinder  is  attached  by  a  rod  to  the  center  of  the  dia- 
phragm. The  cylinder,  and  its  chamber,  E,  will  therefore,  vibrate 
with  the  diaphragm.  A  downward  movement  lets  the  chamber 
communicate  with  the  outlet,  H,  an  upward  movement  with  the 
outlet,  G.  The  compressed  ah-  enters  at  A,  and  fills  the  cham- 
ber, which,  in  its  normal  position,  has  no  outlet.  Every  down- 
ward vibration  of  the  diaphragm  will  thus  condense  the  air  in  the 
pipe,  C,  at  the  same  time  allowing  the  air  in  B  to  escape  via 
F.  An  upward  movement  condenses  the  air  in  C,  but  opens  I. 
The  third  and  last  part  is  shown  in  Fig.  19.  It  consists  of  a 
cylinder,  and  piston,  P,  like  that  employed  hi  an  ordinary  engine. 
The  piston-rod  is  attached  to  the  center  of  a  large  diaphragm  D. 
The  pipes  C  and  B,  are  continuations  of  those  designated  in  Fig. 
1 8,  by  the  same  letters.  The  pipe  C,  communicates  with  one 
chamber  of  the  cylinder,  and  B  with  the  other.  The  piston, 
moving  under  the  influence  of  the  compresssed  air,  moves  also 
the  diaphragm,  its  vibrations  being,  in  number  and  duration, 
identical  with  those  of  the  diaphragm  in  the  mouth-piece. 

The  loudness  of  the  sound  emitted  through  the  directing  tube, 
F,  is  dependent  on  the  size  of  the  diaphragm  and  the  power 
which  moves  it.  The  former  of  them  is  made  very  large,  and 
the  latter  can  be  increased  to  many  hundred  pounds'  pressure. 

With  this  instrument  a  locomotive  may  be  made  to  call  out 
the  stations;  steamships  can  converse  at  sea;  light-houses  may 
thunder  the  notes  of  danger  far  over  the  deep,  and  by  a  single 
machine,  as  Mr.  Edison  says,  "the  Declaration  of  Independence 
may  be  read  so  that  every  citizen  in  any  one  of  our  large  cities 
may  hear  it" 


142 


THOMAS  A.  EDISON 
Edison's  Phonometer. 


SOUND    POWER— A   MECHANISM    RUN   BY   THE    HUMAN   VOICE— How 
DISCOVERED  AND  HOW  IT  is  DONE. 

This  is  a  very  ingenious  and  novel  piece  of  mechanism,  noted 
for  the  singular  fact,  that  when  spoken  or  sung  at,  (or  into,)  res. 
ponds  immediately  by  causing  a  wheel  to  revolve,  but  is  deaf  to  all 
other  influences.  No  amount  of  blowing  will  start  the  wheel; 


The  Phonometer. 

only  by  the  aid  of  sound  can  it  be  set  in  motion.  In  his  tele- 
phone and  phonograph  researches  Mr.  Edison  discovered  that 
the  vibrations  of  the  vocal  chords  were  capable  of  producing 
considerable  dynamic  effect.  Acting  on  this  hint,  he  began  ex- 
periments on  a  phonometer,  or  instrument  for  measuring  the 
mechanical  force  of  sound  waves  produced  by  the  human  voice. 


AND  HIS  INVENTIONS.  143 

In  the  course  of  these  experiments  he  constructed  the  machine 
shown  in  the  accompanying  engraving,  which  exhibits  the  dy- 
namic force  of  the  voice. 

The  machine  has  a  diaphragm  and  mouth-piece  similar  to  a 
phonograph.  A  spring  which  is  secured  to  the  bed  piece  rests 
on  a  piece  of  rubber  tubing  placed  against  the  diaphragm.  This 
spring  carries  a  pawl  L,  that  acts  on  a  ratchet  or  roughened  wheel 
R,  on  the  fly-wheel  shaft.  A  sound  made  in  the  mouth-piece  cre- 
ates vibrations  in  the  diaphragm;  the  vibrations  of  the  dia- 
phragm move  the  spring  and  pawl  with  the  same  impulses,  and 
as  the  pawl  thus  moves  back  and  forth  on  the  ratchet  wheel,  it 
is  made  to  revolve.  It  revolves  with  considerable  power :  for  it 
requires  a  surprising  amount  of  pressure  on  the  fly-wheel  shaft  to 
stop  the  machine  while  a  continuous  sound  is  made  in  the  mouth- 
piece. Mr.  Edison  says  there  is  no  difficulty  in  making  the  ma- 
chine bore  a  hole  through  a  board. 

The  various  purposes  which  this  exeedingly  ingenious  and 
novel  instrument  may  yet  be  called  upon  to  accomplish,  of 
course  are  mere  conjectures,  but  if  confined  to  the  measurement 
of  sound  force  only,  it  is  a  valauble  discovery,  for  in  this  depar- 
ment  it  may  find  many  important  applications. 


144  THOMAS  A.  EDISON 

Edison's  Harmonic  Engine. 

PUMPING   WATER   WITH   A   TUNING   FORK— A    SINGULAR   MACHINE- 
HOW  IT  WORKS. 

Until  recently,   electricity   as   a   motive   power  has   been   a 
comparative   failure   as   ninety  per   cent,    of   the   battery  was 


Fig.  20;  Harmonic  Engine. 

wasted.  Mr.  Edison  has  devised  a  novel  electrical  machine 
which  he  calls  the  Harmonic  Engine,  in  which  ninety  per  cent 
of  the  power  is  realized.  With  two  small  electro-magnets  and 


AND  HIS  INVENTIONS.  145 

three  or  four  small  battery  cells,  sufficient  power  is  generated  to 
drive  a  sewing  machine  or  pump  water  for  household  purposes. 

This  engine,  which  is  shown  in  Fig.  20,  consists  of  a  fork 
which  is  two  feet  and  a  half  long,  made  of  two  inch  square 
steel.  The  curved  part  of  the  fork  is  firmly  keyed  in  a  solid 
casting  which  is  bolted  to  a  suitable  foundation,  and  to  each 
arm  of  the  fork  is  secured  a  thirty-five  pound  weight.  Outside 
of  and  near  the  end  of  each  arm  is  placed  a  very  small  electro- 
magnet. These  magnets  are  connected  with  each  other,  and 
with  a  commutator  that  is  operated  by  one  of  the  arms.  The 
arms  make  thirty-five  vibrations  per  second,  the  amplitude  of 
which  is  one-eighth  of  an  inch.  Small  arms  extend  from  the 
fork  arms  into  a  box  containing  a  miniature  pump  having  two 
pistons,  one  piston  being  attached  to  each  arm.  Each  stroke 
of  the  pump  raises  a  very  small  quantity  of  water,  but  this  is 
compensated  for  by  the  rapidity  of  the  strokes.  Mr.  Edison 
proposes  to  compress  air  with  the  harmonic  engine,  and  use  it 
as  a  motive  agent  for  propelling  sewing  machines  and  other 
light  machinery.  The  power  must  be  taken  from  the  fork  arms 
so  as  not  to  affect  the  synchronism  of  their  vibrations,  otherwise 
this  novel  engine  will  not  operate.  It  appears  to  be  consider- 
ably in  advance  of  other  electric  engines,  and  through  its 
agency  electricity  may  yet  become  a  valuable  motive  power. 

When  we  remember  that  this  engine  is  capable  of  causing  the 
arms  to  make  seventy  or  more  combined  strokes  per  second,  and 
that  each  stroke  can  be  made  to  pump  a  few  drops  of  water,  it 
is  readily  seen  that  as  now  constructed,  the  harmonic  engine  is 
of  no  inconsiderable  value. 


146  THOMAS  A.  EDISON 

Edison's  Motograph  Receiver. 

Mr.  Edison  has  quite  recently  applied  to  his  telephone,  the 
principle  of  his  electro-motograph.  It  is  called  the  "Motograph 
Receiver, "  and  is  described  as  follows : 


The  Motograph  Receiver. 

A  diaphragm  of  mica  four  inches  in  diameter  is  held  in  a  suitable 
framework.  A  hand  crank  or  screw  at  A,  rotates  a  chalk  cyl- 
inder D,  (previously  impregnated  with  the  chemical  solution,) 
with  a  continuous  forward  motion  directly  outward  from  the  face 
of  the  diaphragm.  One  end  of  a  metal  bar  is  fastened  to  the 
center  of  the  diaphragm  and  the  other  end  rests  upon  the  chalk 
cylinder,  being  held  down  very  firmly  by  a  spring.  The  circuit 
is  made  from  this  metal  bar,  through  the  chalk  cylinder  to  the 
base.  As  the  cylinder  is  rotated  either  by  hand  or  other  power 
the  friction  between  the  metal  bar  and  the  chalk  cylinder  is  very 
considerable,  and  the  dhphragm  is  drawn  or  bowed  outward 
toward  the  cylinder.  This  operation  is  purely  mechanical  and 
local.  When  the  electric  waves  are  transmitted  from  the  distant 
station  by  the  speaker  (who  uses  Edison's  carbon  transmitter) 
over  the  wire  to  the  receiver,  each  wave  as  it  passes  through  the 
chalk  cyilinder  effects  by  electro-chemical  decomposition  more 
or  less  neutralization  of  the  friction  between  the  bar  and  the 
cylinder,  according  as  the  wave  may  be  a  strong  or  weak  one. 
The  resultant  effect  of  each  wave  is  the  freeing  of  the  diaphragm, 
permitting  it  to  gain  its  normal  position.  Thus  a  series  of  elec- 
tric waves,  with  the  alternate  space  between,  effects  a  vibration 
of  the  diaphragm  in  perfect  accord  with  the  voice  of  the  speaker. 


AND  HIS  INVENTIONS.  147 

Etheric  Force. 

Sometime  since  Mr.  Edison  and  his  assistants  were  experi- 
menting with  a  vibrator  magnet,  consisting  of  a  bar  of  Stubb's 
steel,  fastened  at  one  end  and  made  to  vibrate  by  means  of  a 
magnet,  when  they  noticed  a  spark  coming  from  the  core  of  the 
magnet.  They  had  often  noticed  the  same  phenomenon  in  con- 
nection with  telegraphic  relays  and  other  electrical  instruments, 
and  had  always  supposed  it  to  be  due  to  inductive  electricity. 
On  this  occasion  the  spark  was  so  bright  that  they  suspected 
something  more  than  mere  induction.  On  testing  the  apparatus 
they  found  that,  by  touching  any  portion  of  the  vibrator  or 
magnet  with  a  piece  of  metal,  they  got  "the  spark!" 

They  then  connected  a  wire  to  the  end  of  the  vibrating  rod — 
the  wire  leading  nowhere — and  got  a  spark  by  touching  the  wire 
with  a  piece  of  iron.  Still  more  remarkable,  a  spark  was  got  on 
turning  the  wire  back  on  itself  and  touching  any  point  of  the 
wire  with  its  free  end !  These  strange  phenomena,  in  which  the 
sparks  as  exhibited  seem  to  antagonize  the  known  laws  of  elec- 
trical science,  led  Mr.  Edison  to  believe  he  had  discovered  a 
new  force.  He  accordingly,  after  repeated  experimentation, 
named  his  discovery  "Etheric  Force." 

It  differs  from  electricity,  especially  inductive  electricity,  to 
which  its  sparks  were  at  first  attributed — in  that  its  sparks  are 
different  in  appearance  and  effect.  They  scintillate,  and  require 
actual  contact  of  the  points  at  which  they  appear.  It  differs 
from  electricity  in  general  in  its  entire  independence  of  polarity. 
It  does  not  require  insulation.  It  will  not  charge  a  Leyden  jar. 
It  has  no  effect  upon  electroscopes  or  galvanometers.  It  fails  to 
affect  chemical  compounds  which  are  extremely  sensitive  to 
electricity.  This  discovery  called  forth  considerable  criticism. 

Edison  says :  I  suggest  that  as  I  have  freely  laid  myself  open 
to  criticism  by  presuming  to  believe  in  the  capacity  of  Nature  to 
supply  a  new  form  of  energy,  which  presumption  rests  upon  ex- 
periment, it  is  but  fair  that  my  critics  should  back  up  their  as- 
sertions by  experiment,  and  give  me  an  equal  chance  as  a  critic. " 


U8  THOMAS  A.  EDISON 

The  Electric  Light. 

TH«  AGES  SLOW  TO  LEARN— EDISON'S  LIGHT  vs.  JABLOCHKOFF'S,  KT  XL- 
SUBDIVISION  OF  THE  FLUID— PLATINUM  AND  IRIDIUM  ESSEN- 
TIAL FACTORS — How  THE  LIGHT  APPEARED  TO 
A  VISITOR — CARBON  CANDLE. 

Electric  light,  though  it  has  been  flashing  from  the  clouds  from 
the  remotest  ages  of  creation,  and  is  in  fact  older  than  the  hills, 
has  not  until  within  a  recent  date  been  considered  of  any  prac- 
tical utility.  Job,  and  Ben.  Franklin,  each  in  his  day,  saw  this 
light,  but  they  never  dreamed  that  it  was  ultimately  to  illumine 
great  cities.  Like  almost  every  other  real  good  in  the  physical 
realm,  this,  too,  has  had  its  long  period  of  in  appreciation  and  non- 
comprehension.  One  would  have  supposed  that  the  rousing  thun- 
ders, Heaven's  great  aerophone,  that  accompanies  every  exhibi- 
bition  of  this  light,  would  have  long  ago,  awakened  the  world 
itself  to  a  realization  of  the  fact  that  the  electric  light  might  be 
utilized.  But  it  has  not  been  so.  Coal,  even — to  say  nothing 
of  coal  gas — is  a  modern  discovery.  So  are  potatoes  and  "love 
apples, "  so  far  as  their  essential  values  are  concerned.  The  ages 
are  slow  to  learn.  And  even  now  there  are  sage  philosophers 
who  stoutly  aver  that  Mr.  Edison  will  never  succeed  with  his 
electric  light.  Probably  it  is  better  to  exercise  even  this  much 
thought  about  a  new  subject  and  so  assert,  than  not  to  think 
anything  whatever  about  the  matter.  So  they  thought  and  as- 
serted about  the  quadruplex,  and  other  of  his  inventions,  and 
yet  they  came  along.  It  will  be  seen  in  another  part  of  this 
volume  that  Mr.  Edison,  while  engaged  on  duplex  transmission, 
was  called  a  lunatic,  and  yet  this  came  out  all  right,  and  he  now 
talks  of  a  sextuplex.  His  quadruplex  system,  says  the  President 
of  the  Western  Union  Telegraph  Company  in  his  last  report, 
"saved  the  Company  five  hundred  thousand  dollars  yearly  in 
construction. "  Splendid  insanity  this,  which  can  accomplish 
such  stupendous  results  financially  from  a  single  invention ! 

The  general  public  wish  Mr.  Edison  all  possible  success  in  this 
new  line  of  investigation,  and  doubtless  believe  it  is  only  a  ques- 


AND  HIS  INVENTIONS.  149 

tion  of  time  when  the  electric  light  will  be  no  longer  confined 
to  flashes  in  the  clouds.  The  logical  position  is  one  of  confident 
expectation.  We  must  wait  and  see.  As  a  matter  of  fact,  Mr. 
Edison,  thus  far,  has  comprehended  the  subject  of  electricity 
sufficiently  to  introduce  into  this  country  more  telegraphic  instru- 
ments than  any  other  man,  and  there  are  more  of  them  earning 
money  to-day  than  of  any  other  man's  inventions.  All  this  is 
encouraging,  to  say  the  least. 

But  Mr.  Edison  has  already  accomplished  very  much  of  what 
is  to  be  done  in  securing  the  electric  light.  The  "subdivision"  is 
a  virtual  fact.  Only  the  details  necessary  to  render  it  easily 
and  safely  manipulated  remain.  And  to  these  points  he  is  giving 
his  patient  attention  and  energy.  So  far  as  he  has  gone  in  the 
great  work,  it  should  be  noted,  that  his  method  radically  differs 
from  all  others.  While  Jablochkoff,  Sawyer,  Werdermann,  Wal- 
lace, Jenkins,  and  others  consume  carbon,  more  or  less,  in  their 
methods  of  electrical  illumination,  Mr.  Edison's  is  one  of  incan- 
descence. They  use  the  carbon  candle,  which  has  not,  thus  far, 
allowed  the  subdivision  of  the  electric  fluid  to  any  great  extent; 
he  uses  a  metalic  compound  which  admits  of  almost  an  infinite 
subdivision,  and  which  is  not  consumed. 

When  an  electrical  current  from  a  battery  meets  with  resis- 
tance to  its  passage,  the  electricity  is  directly  converted  into 
heat.  If  a  thin  wire  be  placed  in  the  circuit  the  temperature  of 
the  wire  rapidly  rises;  and  it  has  long  been  known  that  the 
amount  of  heat  thus  generated  is  directly  proportional  to  the 
electric  resistance  of  the  wire.  Now  the  resistance  depends, 
among  other  things,  on  the  nature  of  the  metal;  those  metals 
which  are  good  conductors,  such  as  silver,  offering  much  less  re- 
sistance than  those  which  are  bad  conductors  such  as  platinum, 
which  from  its  low  electric  conductivity,  or  what  amounts  to 
the  same  thing,  from  its  high  resistance — is  peculiarly  fitted  for 
exhibiting  incandescence.  A  chain  made  of  alternate  links 
of  platinum  and  silver,  when  placed  in  a  circuit  would  show 
the  platinum  links  in  a  state  of  white  heat.  The  resistance 
which  a  platinum  or  other  wire  offers  to  the  current  is  related 


i5o  THOMAS  A.  EDISON 

not  only  to  the  nature  of  the  metal,  but  also  to  the  thickness  of 
the  wire.  Reduce  the  thickness  and  the  resistance  is  immediately 
increased.  Again,  the  heating  effect  is  closely  connected  with 
the  strength  of  the  current.  Hence  a  powerful  current  sent 
through  a  thin  platinum  wire  immediately  renders  it  incan- 
descent (white  heat.) 

Mr.  Edison's  electric  light  is  produced  by  incandescence. — 
The  conductor,  which  is  made  incandescent  by  the  electrical 
current  passing  through  it,  is  a  small,  curiously  shaped  apparatus, 
consisting  of  a  high  alloy  of  platinum  and  iridium,  which  can- 
not be  melted  at  5,000  degrees  Fahrenheit.  A  sufficient  quantity 
of  this  metal  is  placed  in  each  burner  to  give  a  light  equal  to 
that  of  a  gas  jet.  Devices  of  exceeding  simplicity,  and,  as 
repeated  experiments  have  proved,  of  equal  reliability,  are  con- 
nected with  the  lamp.  They  surmount  the  apparent  impossibility 
of  regulating  the  strength  of  the  light.  This  lamp,  when  placed 
in  the  electric  circuit  in  which  a  strong  current  circulates,  is 
absolutely  independent  of  the  strength  of  the  current.  This 
Mr.  Edison  considers  one  of  the  vital  features  of  the  invention. 
Thus,  if  the  regulator  is  set  so  that  the  light  gives  only,  say, 
ten  candle  power,  no  increase  in  the  strenth  of  the  current  will 
increase  its  brilliancy. 

Each  light  is  independent  of  all  others  in  the  circuit.  A 
thousand  may  be  fed  from  the  same  conductor,  and  the  extin- 
guishing of  all  but  one  will  have  on  that  one  Mr.  Edison  claims, 
no  perceptible  effect.  Each  lamp  in  the  circuit,  by  means  of 
the  regulator — a  description  of  which  latter  the  inventor  for  the 
present  withholds — is  allowed  to  draw  from  the  central  station 
just  sufficient  current  to  supply  itself.  In  lighting  by  incandes- 
cence the  light  is  obtained  by  the  resistance  which  the  conduqtor 
in  the  lamp  offers  to  the  passage  of  the  electric  current.  Hence 
any  other  resistance  exterior  to  the  lamp  used  therewith  to  reg- 
ulate it  requires  a  current  in  proportion  to  its  resistance  although 
it  gives  no  light.  One  of  the  main  features  of  Edison's  invention 
consists  in  having  all  the  resistance  outside  of  the  main  conductor 
produce  light,  consequently  there  is  maximum  economy.  The 


AND  HIS  INVENTIONS.  151 

lamp  devised  by  Mr.  Edison  is  not  merely  a  coil  of  incandescent 
metal,  but  a  very  peculiar  arrangement  of  such  metal  whereby 
(by  means  of  a  discovery  of  his  in  connection  with  radiant  en- 
ergy) a  much  weaker  current  is  made  to  generate  a  given  light 
than  if  a  given  spiral  were  used,  and  the  considerable  loss  due  to 
the  division  of  the  light  is  compensated  for. 

In  the  Jablokoff  method  of  electrical  illumination,  now  used 
to  a  limited  extent  in  Europe,  the  carbon  candle,  so  called, 
consists  of  two  rods  or  needles  of  carbon  placed  side  by  side, 
and  kept  insulated  from  each  other,  by  a  layer  of  plaster  paris. 
They  are  each  one-eighth  of  an  inch  in  diameter  and  ten  inches 
long,  and  are  firmly  fixed  into  metal  sockets,  to  which  wires  are 
led  and  the  conductor  of  the  machine  is  made.  When  new,  the 
tops  of  the  two  sticks  only  are  joined  by  a  small  bit  of  carbon. 
One  of  these  will  ordinarily  burn  from  an  hour  and  a  quarter  to 
an  hour  and  a  half.  Four  of  them  are  usually  adjusted  together 
under  a  large  opal  glass  globe  which  subdues  the  dazzling  brill- 
iancy of  the  light,  though  at  a  loss  of  about  one  half  of  the  illu- 
minating power  of  the  naked  candle.  As  one  of  these  candles 
burns  down,  the  current  is  shifted  to  the  next,  and  so  on  until 
the  four  are  consumed.  So  that,  at  the  outside,  the  lamps  would 
continue  burning  six  hours,  when  the  set  of  four  candles  has  to 
be  replaced  by  others.  By  sending  the  current  of  electricity 
alternately  through  the  two  rods,  thereby  changing  the  poles,  the 
carbons  are  kept  uniform  in  length  and  the  light  more  steady. 

It  has  been  acknowledged  by  nearly  all  electricians  that 
lighting  by  incandescence,  especially  incandescence  of  a  metalic 
wire,  offers  less  obstacles  to  the  division  of  the  electric  light  than 
by  any  other  method,  and  Mr.  Edison  believes  it  to  be  the  only 
reliable  method,  because  the  light-giving  metal  is  an  electrical 
"constant"  whose  resistance  can  always  be  known  and  depended 
upon, — a  condition  which  is  exceedingly  essential  when  many 
hundreds  of  lights  must  be  supplied  from  one  conductor.  In  the 
case  of  the  electric  are  between  carbon  rods,  the  resistance 
varies  at  every  instant,  not  only  from  changes  in  the  strength  of 
the  current,  but  from  impurities  in  the  carbon,  from  air-currents, 


152  THOMAS  A.  EDISON 

and  from  many  other  causes.  On  this  account  Mr.  Edison 
claims  that  factors  so  variable  coming  in  play  in  hundreds  of 
lamps  make  it  impossible  to  calculate  the  strength  of  the  current 
or  size  of  the  conductors.  It  would  be  as  difficult  supplying  gas 
from  one  main  where  each  burner  varied  from  excessive  limits 
with  the  rapidity  of  lightning.  Besides  in  the  case  of  carbon 
points  many  hundreds  reacting  on  each  other  cause  such  an  un- 
steadiness in  the  light  as  to  be  unbearable.  Lighting  by  incan- 
descence Mr.  Edison  claims  is  free  from  any  of  these  defects. 

In  the  course  of  his  experiments  on  the  electric  light  Mr.  Edison 
made  the  discovery  that  he  could,  by  a  certain  combination  in 
the  form  of  the  metal  used  in  his  lamp  secure  sufficient  light 
from  the  electricity  generated  from  a  one  cell  battery  to  enable 
him  to-read  by.  The  cell  used  was  an  ordinary  one  of  Daniell's 
battery.  To  his  surprise — for  he  hardly  expected  such  a  result — 
the  metal  soon  became  a  dull  red,  and,  after  several  other  chan- 
ges, he  succeeded  in  obtaining  a  glow  which  made  it  not  at  all 
difficult  to  read  by  the  room  being  kept  dark.  Several  of  the 
labratory  hands  examined  the  phenomenon  with  curiosity.  It 
served  to  demonstrate  to  Mr.  Edison  that  he  had  hit  upon  the 
form  of  metal  to  produce  the  best  result. 

Another  new  feature  in  the  system  of  the  light  as  a  whole  is 
his  improvement  on  dynamo  machine  specifications,  for  a  patent 
for  which  Mr.  Edison  has  only  just  applied. 

A  visitor  at  Menlo  Park  describes  this  light  as  follows: 
Mr.  Edison  exhibited  an  electric  generating  machine.  It  was 
what  is  known  as  the  Wallace  Machine.  A  knot  of  magnets  ran 
around  the  cylinder,  facing  each  other,  and  wires  were  attached 
to  it.  The  great  inventor  slipped  a  belt  over  the  machine,  and 
the  engine  used  in  his  manufactory  began  to  turn  the  cylinder. 
He  touched  the  point  of  the  wire  on  a  small  piece  of  metal  near 
the  window  casing,  and  there  was  a  flash  of  blinding  white  light. 
It  was  repeated  at  each  touch.  "There  is  your  steam  power 
turned  into  an  electric  light,"  he  said,  There  was  the  light, 
clear,  cold  and  beautiful.  The  intense  brightness  was  gone,  and 
there  was  nothing  irritating  to  the  eye.  The  mechanism  was  so 


AND  HIS  INVENTIONS. 


153 


simple  and  perfect  that  it  explained  itself.  The  strip  of  plati- 
num that  acted  as  a  burner  did  not  burn.  It  was  incandescent. 
It  threw  off  a  light  pure  and  white,  and  it  was  set  in  a  gallows- 
like  frame;  but  it  glowed  with  the  phosphorescent  effulgence  of 
the  star  Altair.  You  could  trace  the  veins  in  your  hands  and 
the  spots  and  lines  upon  your  finger  nails  by  its  brightness.  All 
the  surplns  electricity  had  been  turned  off,  and  the  platinum 
shone  with  a  mellow  radiance  through  the  small  glass  globe  that 
surrounded  it.  A  turn  of  the  screw  and  its  brightness  became 
dazzling,  or  reduced  itself  to  the  faintest  glimmer  of  a  glow- 
worm. It  seemed  perfect 


i54  THOMAS  A.  EDISON 

Edison's  Explanation  of  His  Electric  Light. 
How  THE  ELECTRICITY  is  GENERATED— How  THE  LIGHT  is  PRODUCED- 

The  electro-magnetic  machine  for  producing  the  electricity  for 
Edison's  electric  light,  is  described  by  the  great  inventor  in  his 
specifications,  as  follows : 

"It  has  long  been  known  that  if  two  electro-magnets,  or  an 
electro-magnet  and  a  permanent  magnet,  be  drawn  apart  or 
caused  to  pass  by  each  other,  electric  currents  will  be  set  up  in 
the  helix  of  the  electro-magnet.  It  has  also  been  known  that 
vibrating  bodies,  such  as  a  tuning-fork  or  a  reed,  can  be  kept  in 
vibration  by  the  exercise  of  but  little  power.  I  avail  of  these 
two  known  forces,  and  combine  them  in  such  a  manner  as  to 
obtain  a  powerful  electric  current  by  the  expenditure  of  a  small 
mechanical  force.  In  Fig.  23  of  the  drawing,  a  tuning  fork,  02,  is 
represented  as  firmly  attached  to  a  stand,  bz.  This  fork  is  pre- 
ferably of  two  prongs,  but  only  one  might  be  employed  upon  the 
principle  of  a  musical  reed.  The  vibrating  bar  or  fork  may  be 
two  meters  long,  more  or  less,  and  heavy  in  proportion.  It  has 
its  regular  rate  of  vibration  like  a  tuning  fork,  and  the  mechan- 
ism that  keeps  it  in  vibration  is  to  move  in  harmony.  A  crank 
and  revolving  shaft,  or  other  suitable  mechanism,  may  be  em- 
ployed, but  I  prefer  a  small  air,  gas,  or  water  engine,  applied  to 
each  end  of  the  fork.  The  cylinder  ai  contains  a  piston  and  a 
rod,  hi,  that  is  connected  to  the  end  of  the  bar,  and  steam,  gas, 
water  or  other  fluid  under  pressure  acts  within  the  cylinder,  being 
admitted  first  to  one  side  of  the  piston  and  then  the  other  by  a 
suitable  valve;  the  valve  and  directing  rod,  ^2,  are  shown  for 
this  purpose.  The  bar  of  fork,  #2,  may  be  a  permanent  magnet 
or  an  electro-magnet,  or  else  it  is  provided  with  permanent  or 
electro-magnets.  I  have  shown  an  electro-magnet,  ri,  upon  each 
prong  of  the  fork — there  may  be  two  or  more  on  each — and 
opposed  to  these  are  the  cores  of  the  electro-magnets  d. 
Hence  as  the  fork  is  vibrated  a  current  is  set  up  in  the  helix  of 
each  electro  magnet,  d,  in  one  direction  as  the  cores  approach 
each  other,  and  in  the  opposite  direction  as  they  recede.  This 


156  THOMAS  A.  EDISON 

alternate  current  is  available  for  electric  lights,  but  if  it  is  desired 
to  convert  the  current  into  one  of  continuity  in  the  same  direction 
a  commutator  is  employed,  operated  by  the  vibrations  of  the  fork 
to  change  the  circuit  connections  each  vibration,  and  thereby  make 
the  pulsation  continuous  on  the  line  of  one  polarity.  A  ponion 
of  the  current  thus  generated  may  pass  through  the  helixes  of  the 
electro-magnets,  ci,  to  intensify  the  same  to  the  maximum  power 
and  the  remainder  of  the  current  is  employed  for  any  desired 
electrical  operation  wherever  available.  I,  however,  use  the 
same,  especially  with  my  electric  lights,  but  I  remark  that  elec- 
tricity for  such  lights  may  be  developed  by  any  suitable  appara- 
tus. I  have  represented  commutator  springs  or  levers,  c$,  ^4, 
operated  by  rods  that  slide  through  the  levers,  rj,  ^4.  and  by 
friction  move  them.  When  the  prongs,  02,  02,  are  moving  from 
each  other  the  contact  of  levers,  ^3,  ^4,  will  be  with  the  screws, 
40,  41,  and  the  current  will  be  from  line  i,  through  c\  to  c,  thence 
to  ^3  to  41,  43,  and  to  circuit  of  electro-magnets,  d  d,  and  from 
d  dby  42  to  40  ^4,  and  line  as  indicated  by  the  arrows.  When 
the  prongs,  02,  02,  are  vibrating  towards  each  other  the  circuit 
will  be  through  fi,t,  ^3,  42,  in  the  reverse  direction  through  the 
circuit  and  magnets,  d  d,  back  to  43,  and  by  c^  to  line. " 

Fig.  24  shows  the  Edison  lamp,  which  is  thus  described  by  the 
inventor: 

"Platinum  and  other  materials  that  can  only  be  fused  at  a  very 
high  temperature  have  been  employed  in  electric  lights;  but 
there  is  risk  of  such  light-giving  substance  melting  under  the 
electric  energy.  This  portion  of  my  invention  relates  to  the 
regulation  of  the  electric  current,  so  as  to  prevent  the  same  be- 
coming so  intense  as  to  injure  the  incandescent  material.  The 
current  regulation  is  primarily  effected  by  the  heat  itself,  and  is 
automatic.  In  Fig.  24  I  have  shown  the  light  producing  body  as 
a  spiral,  a,  connected  to  the  posts,  b  c,  and  within  the  glass  cyl- 
inder, g.  This  cylinder  has  a  cap,  /,  and  stands  upon  a  base,  m, 
and  for  convenience  a  colum,  n,  and  a  stand,  of  any  suitable 
character  may  be  employed. 

I  remark  further,  it  is  preferable  to  have  the  light  within  a  case 


AND  HIS  INVENTIONS. 


157 


or  globe,  and  that  various  materials  may  be  employed,  such  as 
alum  water,  between  concentric  cylinders,  to  lessen  radiation, 
retain  the  heat,  and  lessen  the  electric  energy  required;  or  color- 
ed or  opalescent  glass,  or  solutions  that  reduce  the  refrangibility 


Fig.  24;  Edison's  Electric  Light. 

of  the  light,  such  as  sulphate  of  quinine,  may  be  employed  to 
moderate  the  light,  and  the  light  may  either  be  in  the  atmosphere 
pr  in  a  vacuum. 


158  THOMAS  A.  EDISON 

The  electric  circuit,  Fig.  24,  passes  by  line  i  to  the  lever,  / 
thence  by  a  wire  or  rod,  k,  cap  /,  wire,  ^,  to  post,  t,  through  the 
double  spiral,  a,  to  the  post,  If,  and  by  a  metallic  connection  or 
wire  to  line  4,  and  so  on  through  the  electric  circuit  (Lines  i 
and  4,  are  the  same  in  both  figures.)  The  light  is  developed  at  a. 
The  rod,  k,  will  expand  in  proportion  to  the  heat  of  the  coil,  or 
in  proportion  to  the  heat  developed  by  the  passage  of  the  cur- 
rent through  the  fine  wire,  k,  and,  if  the  heat  becomes  danger- 
ously high,  injury  to  the  apparatus  is  prevented  by  the  expansion 
of  rod,  k,  moving  the  lever,  /,  to  close  the  circuit  at  *  and  short 
circuit  or  shunt  a  portion  of  the  current  from  the  coil,  <z,  and 
reducing  its  temperature;  this  operation  is  automatic,  and  forms 
the  principal  feature  of  my  invention,  because  it  effectually  pre- 
serves the  apparatus  from  injury.  The  current  need  not  pass 
through  the  wire  or  rod,  k,  as  the  expansion  thereof  by  the  radi- 
ated heat  from  the  coil,  a,  will  operate  the  lever,  /,  but  the 
movement  is  not  so  prompt.  It  is  to  be  understood  that  in  all 
cases  the  action  of  the  short  current  through  the  light-giving 
substance  and  the  circuit-closing  devices  play  up  and  down  at 
the  contact  point,  maintaining  uniformity  of  brilliancy  of  light." 

Concerning  this  wonderful  invention,  Mr.  Edison  further  states : 
"Electric  light  coils  may  be  put  in  a  secondary  circuit  containing 
cells,  with  plates  in  a  conducting  liquid;  and  a  lever  is  vibrated 
by  an  electro-magnet  or  by  clock-work.  When  the  lever  is 
in  contact  the  current  from  line  i  passes  through  the  electro- 
magnet and  cells,  but  when  the  contact  ceases  the  line  is  closed, 
but  a  local  circuit  is  made  through  the  coils  and  second  battery ; 
the  discharge  of  the  second  battery  gives  the  light,  and  the 
movement  is  so  rapid  that  the  light  appears  continuous."  Thus 
it  will  be  seen  that  Mr.  Edison  is  making  sure  and  steady  pro- 
gress with  his  electric  light,  which  when  finally  completed,  must 
rank  with  the  grandest  of  all  human  inventions.  His  knowledge 
of  the  general  subject,  in  which  he  has  no  superior  in  the  world, 
his  great  inventive  genius,  his  untiring  industry,  personal  interest, 
and  the  success  already  attained,  augur  almost  the  absolute  cer- 
tainty that  the  electric  light  will  soon  be  a  household  blessing. 


AND  HIS  INVENTIONS.  159 


FURTHER  EXPERIMENTS, 


Edison's  New  and  Perfected  Electric  Light— Simplicity  Simplified 
—Making  Little  Suns  Out  of  Burnt  Paper. 

Incredible  as  it  may  appear,  Mr.  Edison's  new  and  perfected 
electric  light  is  produced  from  a  little  piece  of  burnt  paper, 
that  a  single  breath  of  air  would  blow  away.  Through  this  lit- 
tle strip  of  paper  is  passed  an  electric  current,  and  the  result 
is  a  bright,  beautiful  light  like  the  mellow  sunset  of  an  Italian 
autumn.  Mr.  Edison  makes  this  little  piece  of  paper  more 
infusible  than  platinum,  more  durable  than  granite.  And  this 
involves  no  complicated  process. 

The  paper  is  merely  baked  in  an  oven,  until  all  its  elements 
have  passed  away  except  its  carbon  framework.  The  latter  is 
then  placed  in  a  glass  globe,  connected  with  the  wires  leading 
to  the  electricity  producing  machine,  and  the  air  exhausted 
from  the  globe.  Then  the  apparatus  is  ready  to  give  out  a 
light  that  produces  no  deleterious  gases,  no  smoke,  no  offensive 
odors — a  light  without  flame,  without  danger — requiring  no 
matches  to  ignite,  giving  out  but  little  heat,  vitiating  no  air, 
and  free  from  all  flickering;  alight  that  is  a  little  globe  of  sun- 
shine, a  veritable  Aladdin's  lamp. 

In  the  preceding  pages  which  treat  of  the  electric  light,  we 
have  the  steps  taken  by  Mr.  Edison,  that  led  him  through  a 
maze  of  experiments  up  to  his  "  platinum  burner,"  which  he 
supposed,  for  a  time,  would  prove  permanently  successful.  It 
was  found,  however,  that  platinum,  when  exposed  to  a  high 
degree  of  heat  for  any  considerable  time  became  crystallized,  a 
condition  unfavorable  for  illumination.  He  therefore  made  a 
new  departure,  the  steps  of  which  are  shown  in  the  following 
pages,  and  which  led  him  to  his  present  Carbon  Lamp. 


i6<s  THOMAS  A.  EDISON 

After  various  experiments  he  hit  upon  the  unique  idea  of 
making  the  platinum  give  the  light  as  it  were  by  proxy.  By 
means  of  a  reflector  he  concentrated  the  heat  rays  of  the  plati- 
num upon  a  piece  of  zircon,  causing  the  latter  to  become  lumin- 
ous. Figure  25  shows  the  apparatus;  a,  is  a  mass  of  non-con- 
ducting material,  b,  is  an  air  space,  c,  is  a  polished  reflector  of 
copper,  coated  with  gold,  d,  is  a  platinum  iridium  spiral,  which 
becomes  heated  by  the  passage  of  the  electric  current  through 
it;  e,  is  a  thin  piece  of  zircon  that  receives  the  heat  rays  thrown 
off  by  the  reflector  c,  which  heat  rays  bring  up  the  zircon  e, 

to  vivid  incandescence, 
making  it  give  out  a 
light  much  more  bril- 
liant than  the  light  of 
the  platinum  spiral,  d. 
With  this  form  Mr. 
Edison  tried  numerous 
experiments,  and  from 
time  to  time  made  many 
alterations  and  improve- 
ments, but  eventually 
the  apparatus  was 
placed  in  the  category 
of  non-successors. 
Realizing  from  the 

Fig.  25,  Zircon  Burner.  first  the  necessity  of  the 

light-giving  substance  offering  much  resistance  to  the  passage 
of  the  electric  current,  a  necessity  in  extensive  subdivision  of 
the  light,  the  inventor  throughout  his  experiments  kept  a  close 
watch  for  substances  and  forms  that  gave  suitable  resistance 
In  figure  26  is  shown  a  form  of  lamp  disconnected  from  the  reg- 
ulating apparatus,  which  largely  embodied  the  above  require- 
ment, and  for  a  time  gave  good  results.  A,  is  a  spiral  of  carbon 
with  two  large  ends,  B,  e,  connecting  with  the  wires  leading  to 


AND  HIS  INVENTIONS.  161 

the  machine  for  generating  the  current.     This  device  was  tried 
for  several  weeks,  but  did  not  as  a  whole  give  satisfaction 

Branching  off  from  the  line  of  investigation  he  had  been  pre- 
viously following,  Mr.  Edison  at  this  time  began  experimenting 
with  a  view  to  having  the  light  produced  locally,  /.  e.,  arrang- 
ing for  each  householder  to  become  his  own  manufacturer  of 
light,  thus  dispensing  with  mains 
and  central  stations.  The  appar- 
atus which  he  used  for  this  purpose 
is  shown  in  figure  27.  R,  is  an  induc- 
tion coil,  such  as  are  used  by  show- 
men at  fairs  and  other  places,  when 
they  give  electric  shocks  to  inquir- 
ing sight-seers  at  so  much  per  shock. 
It  is  operated  by  two  cells  of  bat- 
tery B,  and  wires  lead  from  it  to 
the  glass  tubing  T,  from  which  the 
air  has  previously  been  extracted, 
and  the  passage  of  the  electric  cur- 
rent through  the  tubing  gives  out  a 

ig.  26,  Carbon  Spiral.  light.  This  plan  is  analogous  to  what 

is  known  as  the  Geisler  tube  arrangement,  the  difference  being  in 
the  tube  and  the  extreme  smallness  of  the  bore,  and  also  in  the 
degree  of  vacuum  pro- 
duced. Mr.  Edison  suc- 
ceeded by  this  arrange- 
ment in  obtaining  a  light 
of  several  candle  power, 
with  a  moderately  pow- 
erful induction  coil. 
The  light,  however,  was 
not  the  one  sought  a/ter 
so  persistently  by  the  Fig.  27,  Local  Lamp, 

inventor,  and  so  it  took  its  place  in  that  part  of  the  laboratory 
occupied  by  inventions  not  in  use. 


1 62  THOMAS  A.  EDISON 

Once  more  Mr.  Edison  made  a  departure.  He  molded 
powdered  metallic  oxides  in  the  form  of  sticks,  and  subjected 
them  to  a  very  high  temperature.  In  this  connection  he  ob- 
tained very  fine  results  from  the  native  alloy  of  osmium  iridium 
called  bridosmine,  which  alloy  he  used  in  the  form  of  a  powder 
inclosed  in  a  tube  of  zircon.  The  electric  current  passing 
through  the  same  brought  it  to  a  beautiful  incandescence. 

The  inventor's  next  important  move  was  the  adoption  of  car- 
bon in  connection  with  platinum  as  the  substance  to  be  made 
incandescent.  He  caused  a  slender  rod  of  carbon  to  rest  upon 
another  of  platinum,  the  inferiority  of  contact  between  the  two 
at  their  point  of  meeting  producing  a  resistance  to  the  passage 
of  the  electric  current  and  causing  the  carbon  to  become  highly 
incandescent  while  the  platinum  attained  only  a  dull  red  heat. 
The  carbon  rod  was  kept  pressing  upon  the  platinum  by  a 
weight  ingeniously  arranged.  A  dozen  or  more  forms  of  this 
lamp  were  made,  but  after  all  the  inventor  was  obliged  to 
return  to  platinum  as  the  substance  most  suited,  all  things  con- 
sidered, for  being  made  incandescent.  For  two  months  he 
worked  at  platinum,  day  and  night,  only  to  find  that  platinum, 
as  he  had  previously  been  using  it,  was  worthless  for  incandes- 
cent lighting.  To  many  experimenters  this  would  have  proved 
a  discouragement  perhaps  fatal,  but  it  had  the  effect  only  of 
increasing  Edison's  determination,  and,  after  scores  of  new  ex- 
periments, he  arrived  at  the  true  causes  of  the  defects,  and 
hastened  to  apply  the  remedy.  "  I  have  found,"  he  writes, 
"  that  when  wires  or  sheet  platinum,  iridium,  or  other  metallic 
conductors  of  electricity,  that  fuse  at  a  high  temperature,  are 
exposed  to  a  high  temperature  near  their  melting  point  in  air 
for  several  hours,  by  passing  a  current  of  electricity  through 
them,  and  then  are  allowed  to  cool,  the  metal  is  found  to  be 
ruptured,  and  under  the  microscope  there  are  revealed  myriads 
of  cracks  in  various  directions,  many  of  which  reach  nearly  to 
the  center  of  the  wire.  I  have  also  discovered  that,  contrary 
to  the  received  notion,  platinum  or  platinum  and  iridium  alloy, 


AND  HIS  INVENTIONS.  163 

loses  weight  when  exposed  to  the  heat  of  a  -candle ;  that 
even  heated  air  causes  it  to  lose  weight ;  that  the  loss  is  so 
great  a  hydrogen  flame  is  tinged  green.  After  a  time  the  metal 
falls  to  pieces ;  hence  wire  or  sheets  of  platinum  or  platinum 
and  indium  alloy,  as  now  known  in  commerce,  are  useless  for 
giving  light  by  incandescence:  i.  Because  the  loss  of  weight 
makes  it  expensive  and  unreliable,  and  causes  the  burner  to  be 
rapidly  destroyed.  2.  Because  its  electrical  resistance  changes 
by  loss  in  weight,  and  its  light-giving  power  for  the  total  sur- 
face is  greatly  reduced  by  the  cracks  and  ruptures.  The  melt- 
ing point  also  is  determined  by  the  weakest  spot  of  the  metal. 

"By  my  invention  or  discovery  I  am  able  to  prevent  the 
deterioration  of  the  platinum  or  its  alloy  by  cutting  off  or  inter- 
cepting the  atmospheric  action.  A  spiral  wire  or  other  forms 
of  platinum  is  placed  in  a  glass  tube  or  bulb,  with  the  wire 
near  its  ends  passing  through  and  sealed  in  the  glass,  and  the 
air  is  exhausted  from  the  glass.  The  platinum  wires  of  the 
spiral  are  then  connected  to  a  magneto-electric  machine  or 
battery,  the  current  of  which  can  be  controlled  by  the  addition 
of  resistance.  Sufficient  current  is  allowed  to  pass  through  the 
wire  to  bring  it  to  about  150  degrees  Fahrenheit.  It  is  then 
allowed  to  remain  at  this  temperature  ten  or  fifteen  minutes. 
While  thus  heated,  both  the  air  and  gases  confined  in  the  metal 
are  expelled  by  the  heat  or  withdrawn  by  the  vacuum  action. 

"  While  this  air  or  the  gases  are  passing  out  of  the  metal  the 
mercury  pump  is  kept  continually  working. 

"  After  the  expiration  of  about  fifteen  minutes,  the  current 
passing  through  the  metal  is  augmented  so  that  its  temperature 
will  be  about  300  degrees  Fahrenheit,  and  it  is  allowed  to  re- 
main at  this  temperature  for  another  ten  or  fifteen  minutes. 

"  The  mercury  pump  is  to  be  worked  continuously,  and  the 
temperature  of  the  spiral  raised  at  intervals  of  ten  or  fifteen 
minutes,  until  it  attains  vivid  incandescence  and  the  glass  is 
contracted  where  it  has  passed  to  the  pump  and  melted  to- 
gether, so  that  the  wire  is  in  a  perfect  vacuum,  and  in  a  state 


164  THOMAS  A.  EDISON 

heretofore  unknown,  for  it  may  have  its  temperature  raised  to 
a  most  dazzling  incandescence,  emitting  a  light  of  twenty-five 
standard  candles,  whereas,  before  treatment,  the  same  radiating 
surface  gave  a  light  of  only  about  three  standard  candles.  The 
wires,  after  being  thus  free  from  gasses,  are  found  to  have  a 
polish  exceeding  that  of  silver,  and  obtainable  by  no  other 
means.  No  cracks  can  be  seen  even  after  the  spiral  has  been 
raised  suddenly  to  incandescence  many  times  by  the  current, 
and  the  most  delicate  balance  fails  to  show  any  loss  of  weight 
in  the  wire  even  after  it  is  burning  for  many  hours  continuously. 
I  have  further  discovered  that  if  an  alloy  of  platinum  and  irid- 
ium  coated  with  the  oxide  of  magnesium  and  subjected  to  the 
vacuum  process  described,  a  combination  takes  place  between 
the  metal  and  the  oxide,  giving  the  former  remarkable  proper- 
ties. With  a  spiral  having  a  radiating  surface  of  three-sixteenths 
of  an  inch,  light  equal  to  that  given  by  forty  standard  candles 
may  be  obtained,  whereas,  the  same  spiral,  not  coated 
by  any  process,  would  melt  before  giving  a  light  of  four 
candles. 

"The  effect  of  the  oxide  of  magnesium  is  to  harden  the  wire 
to  a  surprising  extent,  and  render  it  more  refractory.  A  spiral 
made  of  this  wire  is  elastic  and  springy  when  at  high  incandes- 
cence. I  have  found  that  chemically  pure  iron  and  nickel, 
drawn  in  wires  and  subjected  to  the  vacuum  process,  may  be 
made  to  give  a  light  equaling  that  of  platinum  in  the  open-air. 
Carbon  sticks  also  may  be  freed  from  air  in  this  manner,  and 
be  brought  to  a  temperature  where  the  carbon  becomes  pasty, 
and  on  cooling  it  is  homogeneous  and  hard." 

About  this  time  another  truth  dawned  upon  the  inventor, 
viz.,  that  economy  in  the  production  of  light  from  incandes- 
cence demanded  that  the  incandescence  substance  offer  a 
very  great  resistance  to  the  passage  of  the  electric  current. 
Concerning  this  the  inventor  writes  :  "  It  is  essential  to  re- 
verse the  present  practice  of  having  lamps  of  but  one  or  two 
ohms  (electrical  units)  resistance,  and  construct  lamps  which, 


AMD  HIS  INVENTIONS. 


when  giving  their  proper 
light,  shall  have,  at  least, 
200  ohms  resistance." 

The  lamp,  at  this  stage 
is  shown  in  figure  28.  a, 
is  the  burner,  or  incan- 
descent platinum,  in  the 
shape  of  a  bobbin,  sup- 
ported within  the  vac- 
uum tube  b,  by  a  rod  d, 
of  the  same  material  as 
the  bobbin  ;  the  vacuum 
tube  b,  is  sustained  by 
the  case  K,  and  around 
said  tube  b,  is  a  glass 
globe,  I;  within  the  case 
K,  is  a  flexible  metallic 
aneroid  chamber,  L,  that 
opens  into  the  glass  case 
I,  so  that  the  air,  when 
expanded  by  heat,  can 
pass  into  the  aneroid 
chamber  and  give  mo- 
tion to  the  flexible  di- 
aphragm, X,  and  parts 
connected  therewith. 

When  the  current  cir- 
culating around  the  bob- 
bin a,  becomes  too  in- 
tense, the  air  within  th^ 
glass  case  I  is  expanded, 
and  presses  the  dia- 
phragm X  and  the  pin 
upon  the  spring  5,  and 


166  THOMAS  A.  EDISON 

separates  said  spring  from  the  block  6,  and  breaks  the  cir- 
cuit to  the  burner.  The  temperature  within  the  globe  I,  lowers 
immediately,  and  the  parts  return  to  their  normal,  position, 
closing  the  circuit  through  the  burner  to  5  and  6.  This  open- 
ing and  closing  of  the  circuit  is  but  momentary,  and  the 
uniform  brilliancy  of  the  light  is  not  affected. 

The  lamp,  after  these  latter  improvements,  was  in  quite  a 
satisfactory  condition,  and  the  inventor  contemplated  with 
much  gratification,  the  near  conclusion  of  his  labors.  One  by 
one  he  had  overcome  the  many  difficulties  that  lay  in  his  path. 
He  had  brought  up  platinum  as  a  substance  for  illumination 
from  a  state  of  comparative  worthlessness  to  one  well  nigh 
perfection.  He  had  succeeded,  by  a  curious  combination  and 
improvement  in  air  pumps,  in  obtaining  a  vacuum  of  nearly 
one-millionth  of  an  atmosphere,  and  he  had  perfected  a  gen- 
erator, or  electricity  producing  machine  (for  all  the  time  he  had 
been  working  at  lamps  he  was  also  experimenting  in  magneto- 
electric  machines)  that  gave  out  some  90  per  cent  in  electricity 
of  the  energy  it  received  from  the  driving  engine.  In  a  word, 
all  the  serious  obstacles  toward  the  success  of  incandescent 
electric  lighting  he  believed  had  melted  away,  and  there  re- 
mained but  a  comparatively  fe-v  minor  details  to  be  arranged 
before  his  laboratory  was  to  be  thrown  open  for  public  inspec- 
tion, and  the  light  given  to  the  world  for  better  or  for  worse. 

There  occurred,  however,  at  this  juncture  a  discovery  that 
materially  changed  the  system  and  gave  a  rapid  stride  toward 
the  perfect  electric  lamp.  Sitting  one  night  in  his  labora- 
tory, reflecting  on  some  of  the  unfinished  details,  Edison 
began  abstractedly  rolling  between  his  fingers  a  piec*  of  com- 
pressed lamp  black  mixed  with  tar,  for  use  in  his  telephone. 
For  several  minutes  his  thoughts  continued  far  away,  his  fin- 
gers, in  the  meantime,  mechanically  rolling  out  the  little  piece 
of  tarred  lamp  black  until  it  had  become  a  slender  filament. 
Happening  to  glance  at  it,  the  idea  occurred  to  him  that  it 
might  give  good  results  as  a  burner  if  made  incandescent.  A 


AND  HIS  INVENTIONS.  167 

few  minutes  later  the  experiment  was  tried,  and  to  the  inven- 
tor's gratification,  satisfactory,  although  no  surprising  results 
were  obtained. 

Further  experiments  were  made  with  other  forms  and  com- 
positions of  the  substance,  each  experiment  demonstrating  that 
at  last  the  inventor  was  upon  the  right  track.  A  spool  of  cot- 
ton thread  lay  on  the  table  in  the  laboratory.  The  inventor 
cut  off  a  small  piece,  put  it  in  a  groove  between  two  clamps  of 
iron  and  placed  the  latter  in  the  furnace.  The  satisfactory 
light  obtained  from  the  tarred  lamp  black  had  convinced  him 
that  filaments  of  carbon  of  a  texture  not  previously  used  in 
electric  lighting  were  the  hidden  agents  to  make  a  thorough 
success  of  incandescent  lighting,  and  it  was  with  this  view  that 
he  sought  to  test  the  carbon  remains  of  a  cotton  thread.  At 
the  expiration  of  an  hour  he  removed  the  iron  mold  contain- 
ing the  thread  from  the  furnace  and  took  out  -the  delicate  car- 
bon frame-work  of  the  thread,  all  that  was  left  of  it  after  its 
fiery  ordeal. 

This  slender  filament  he  placed  in  a  globe,  and  connected  it 
with  the  wires  leading  to  the  machine  generating  the  electric 
current.  Then  he  extracted  the  air  from  the  globe  and  turned 
on  the  electricity.  Presto  !  a  beautiful  light  greeted  his  eyes. 
He  turns  on  more  current,  expecting  the  fragile  filament  in- 
stantly to  fuse.  But  no ;  the  only  change  is  a  more  brilliant 
light.  He  turns  on  more  current,  and  still  more,  but  the  deli- 
cate thread  remains  the  same.  Then,  with  characteristic 
impetuosity,  and  wondering  and  marvelling  at  the  strength  of 
the  little  filament,  he  turns  on  the  full  power  of  his  machine, 
and  eagerly  watches  the  consequence.  For  a  minute  or  more 
the  slender  thread  seems  to  struggle  with  the  intense  heat  pass- 
ing through  it — heat  that  would  melt  the  diamond  itself.  Then 
at  last  it  surcombs,  and  all  is  darkness. 

The  powerful  current  had  broken  it  in  twain,  but  not  before 
it  had  emitted  a  light  of  several  gas  jets.  Eagerly  the  inven- 
tor hastened  to  examine  under  the  microscope  this  curious  fila- 


1 68  THOMAS  A.  EDISON 

ment,  apparently  so  delicate,  but  in  reality  much  more  infusible 
than  platinum,  so  long  considered  one  of  the  most  infusible  of 
metals.  The  microscope  showed  the  surface  of  the  filament  to 
be  highly  polished,  and  its  parts  interwoven  with  each  other. 

It  was  also  noticed  that  the  filament  had  attained  a  remark- 
able degree  of  hardness  compared  with  its  fragile  character 
before  it  was  subjected  to  the  action  of  the  current.  Night 
and  day,  with  scarcely  rest  enough  to  eat  a  hasty  meal  or  catch 
a  brief  repose,  the  inventor  kept  up  his  experiments,  and  from 
carbonizing  pieces  of  thread  he  went  to  splinters  of  wood, 
straw,  paper,  and  many  other  substances  never  before  used  for 
that  purpose.  The  results  of  his  experiments  showed  that  the 
substance  best  adapted  for  carbonization  and  the  giving  out  of 
incandescent  light  was  paper,  preferably  thick  like  cardboard, 
but  giving  good  results  even  when  very  thin.  The  beautiful 
character  of  the  illumination,  and  the  steadiness,  reliability, 
and  non-infusibility  of  the  carbon  filament,  were  not  the  only 
elements  incident  to  the  new  discovery  that  brought  joy  to  the 
heart  of  Edison.  There  was  a  further  element  not  the  less 
necessary  because  of  its  being  hidden,  the  element  of  a  proper 
and  uniform  resistance  to  the  passage  of  the  electric  current. 

The  inventor's  efforts  to  obtain  this  element  had  been  by  far 
the  most  laborious  of  any  in  the  history  of  his  work  from  the 
time  he  undertook  the  task,  and  without  it  absolute  success  to 
electric  incandescent  illumination  could  not  be  predicated,  even 
though  all  the  other  necessary  properties  were  present  in  the 
fullest  degree. 

Passing  over  the  scores  of  experiments  made  since  the  dis- 
covery that  the  carbon  frame-work  of  a  little  piece  of  paper  or 
thread  was  the  best  substance  possible  for  incandescent  ligh* 
ing,  we  come  to  consider  the  way  in  which  the  same  is  prepared 
at  the  present  time  in  the  laboratory. 

With  a  suitable  punch  there  is  cut  from  a  piece  of  "  Bristol " 
card-board  a  strip  of  the  same,  in  the  shape  of  a  miniature 


AND  HIS  INVENTIONS.  169 

horse-shoe,  about  two  inches  in  length  and  one  eighth  of  an 
inch  in  width.  A  number  of  these  strips  are  laid  flatwise  in  a 
wrought-iron  mold  about  the  size  of  the  hand  and  separated 

from  each  other  by  tis- 
sue paper.  The  mold 
is  then  covered  and 
placed  in  an  oven, 
where  it  is  gradually 
raised  to  a  tempera- 
ture of  about  600  de- 
grees Fahrenheit.  This 
allows  the  volatile  por- 
tions of  the  paper  to 
pass  away.  The  mold 
is  then  placed  in  a  fur- 
nace and  heated  almost 
to  a  white  heat,  and 
then  removed  and  al- 
lowed to  cool  gradu- 
ally. On  opening  the 
mold  the  charred  re- 
mains of  the  little 
horse-shoe  card-board 
are  found.  It  must  be 
taken  out  with  the 
greatest  care,  else  it  will 
fall  to  pieces.  After  be- 
ing removed  from  the 
mold  it  is  placed  in  a 
little  globe  and  attach- 

Fig.  29,  Electric  Lamp. 

ed  to  the  wires  leading 

to  the  generating  machine.  The  globe  is  then  connected  with 
an  air-pump,  and  the  latter  is  at  once  set  to  work  extracting 
the  air.  After  the  air  has  been  extracted  the  globe  is  sealed, 
and  the  lamp  is  ready  for  use.  Figure  29  shows  the  lamp  com- 


t;o  THOMAS  A.  EDISON 

plete.  A,  is  a  glass  globe,  from  which  the  air  has  been  extracted, 
resting  on  a  stand,  B.  F,  is  a  little  carbon  filament  connected 
by  fine  platinum  wires  (G,  G  i)  to  the  wires  (E,  E  i)  leading  to 
the  screw-posts  (D,  D  i),  and  thence  to  the  generating  machine. 
The  current  entering  at  D,  passes  up  the  wire  (E)  to  the  plat- 
inum clamp  (G),  thence  through  the  carbon  filament  F,  to  G  i 
down  the  wire  E  i  to  the  screw-post  D  i,  thence  to  the  gener- 
ating machine.  It  will  be  noticed  by  reference  to  the  complete 
lamp  in  figure  29  that  it  has  no  complex  regulating  apparatus, 
such  as  characterized  the  inventor's  earlier  labors.  All  the 
work  he  did  on  regulators  was  practically  wasted,  for  he  has 
lately  realized  that  they  were  not  at  all  necessary,  no  more  so 
than  a  fifth  wheel  is  to  a  coach. 

The  electric  energy  can  be  regulated  with  entire  relia- 
bility at  the  central  station,  just  as  the  pressure  of  gas  is  now 
regulated.  By  his  system  of  connecting  the  wires  the  extin- 
guishment of  certain  of  the  burners  affect  the  others  no  more 
than  the  extinguishment  of  the  same  number  of  gas-burners 
affect  those  drawing  their  supply  from  the  same  main.  The 
simplicity  of  the  completed  lamps  seem  certainly  to  have  ar- 
rived at  the  highest  point,  and  Edison  asserts  that  it  is  scarcely 
possible  to  simplify  it  more.  The  entire  cost  of  construction  is 
not  more  than  twenty-five  cents. 

The  lamp  shown  in  figure  29  is  a  table  lamp.  For  chande- 
liers it  consists  of  only  the  vacuum,  globe,  and  the  carbon 
filament  attached  to  the  chandelier,  and  connected  to  the  wires 
leading  to  the  generating  machine  in  a  central  station,  perhaps 
a  half  a  mile  away,  the  wires  being  run  through  the  gas  pipes, 
so  that  in  reality  the  only  change  necessary  to  turn  a  gas  jet 
into  an  electric  lamp  is  to  run  the  wires  through  the  gas  pipes, 
take  off  the  jet,  and  screw  the  electric  lamp  in  the  latter' s  place. 
Although  the  plans  have  not  been  fully  consummated  for  gen- 
eral illumination,  the  outline  of  the  probable  system  to  be 
adopted  is  the  locating  of  a  central  station  in  large  cities  m 


AND  HIS  INVENTIONS.  ijt 

such  a  manner  that  each  station  will  supply  an  area  of  about 
one  third  of  a  mile. 

In  each  station  there 
will  be,  it  is  contemplated, 
one  or  two  engines  of  im- 
mense power,  which  will 
drive  several  generating 
machines,  each  generat- 
ing machine  supplying 
about  fifty  lamps. 

Mr.  Edison's  first  exper- 
iment in  machines  for  gen- 
erating the  electric  current 
did  not  meet  with  success. 
His  primal  apparatus  was 
in  the  form  of  a  large  tun- 
ing fork,  constructed  in 
such  a  way  that  its  ends 
vibrated  with  great  ra- 
pidity before  the  poles  of 
a  large  magnet.  These 
vibrations  could  be  pro- 
duced with  comparatively 
little  power.  Several 
weeks  of  practice  proved, 
however,  that  the  machine 
was  not  practical,  and  it 
was  laid  aside. 

Then  followed  a  num- 
ber of  other  forms,  lead- 
ing up  gradually  to  the 

D,  The  New  Generator. 

one  at  present  used.  Bear- 
ing in  mind  the  principle  common  to  all  magneto-electric 
machines,  viz.,  that  the  current  is  produced  by  the  rotation  of 
magnets  near  each  other,  it  will  not  be  difficult  to  understand  in 


i7 2  THOMAS  A.  EDISON 

a  general  way  how  his  machine  operates.  It  is  called  the  Far- 
adic  machine,  in  honor  of  Faraday,  and  is  composed  of  two  up- 
right iron  columns,  three  feet  high  and  eight  inches  in  diameter, 
wound  with  coarse  wire,  and  resting  upon  the  bases  which  form 
its  magnetic  poles.  This  part  of  the  apparatus  is  called  the 
field  of  force  magnet.  Fixed  on  an  axle  so  as  to  freely  revolve 
between  the  poles  is  a  cylindrical  armature  of  wood,  wound 
parallel  to  its  axes  with  fine  iron  wire.  When  this  cylinder  or 
armature  is  made  to  revolve  rapidly  between  the  magnetic  poles, 
by  means  of  a  belt  driven  by  an  engine,  there  is  generated  in 
the  wire  surrounding  the  armature  strong  currents  of  electricity, 
which  are  carried  off  by  the  wires  to  the  electric  lamps. 

By  constructing  the  machine  in  the  form  shown  in  figure  30, 
there  is  obtained  an  electric  motor  capable  of  performing  light 
work,  such  as  running  sewing  machines  and  pumping  water. 
It  forms  part  of  the  inventor's  system,  and  may  be  used  either 
with  or  without  the  electric  light. 

To  run  an  ordinary  sewing  machine  it  requires  only  as  much 
electricity  as  is  necessary  to  give  out  one  electric  light  of  the 
strength  of  a  common  gas  jet.  To  put  it  in  operation  on  a 
sewing  machine  the  housewife  has  merely  to  attach  it  by  a  lit- 
tle belt  at  A,  with  the  wheel  of  the  sewing  machine  and  turn  on 
the  electricity  by  touching  a  little  knob  conveniently  attached. 
The  cost  is  the  same  as  if  she  were  burning  one  electric  light. 

The  apparatus  for  measuring  the  amount  of  electricity  used 
by  each  householder  is  a  simple  contrivance,  consisting  of  an 
electrolytic  cell  and  a  small  coil  of  wire  appropriately  arranged 
in  a  box,  the  latter  being  of  about  one  half  the  size  of  an  ordi- 
nary gas  meter,  and,  like  a  gas  meter,  it  may  be  placed  in  any 
part  of  the  house.  The  measurement  is  obtained  by  the  deposit 
of  copper  particles  on  a  little  plate  in  the  electrolytic  cell,  each 
deposit  being  cause']  by  the  electric  current  passing  through 
the  cell.  At  the  end  of  any  period,  say  one  month,  the  plate 
is  taken  by  the  inspector  to  the  central  office,  where  the  copper 
deposit  is  weighed,  and  the  amount  of  electricity  consumed 
determined  by  a  simple  calculation. 


AND  HIS  INVENTIONS. 


173 


The  New  Edison   Dynamo. 

A  WONDERFUL  MECHANISM  FOB  GENERATING  ELECTRICITY. 

The  new  Edison  Dynamo  is  a  singular  and  somewhat 
complicated  mechanism,  which,  by  the  very  rapid  revolu- 
tion of  an  armature,  properly  adjusted  to  a  magnetic  field, 
generates  electricity.  Apparently  this  electricity  comes  from 
the  atmosphere,  or  from  without  the  dynamo  in  some  mys- 
terious manner,  not  yet  fully  understood.  In  the  Edison 


Fig.  81;  Edison  Dynamo. 

Dynamo,  we  have  a  strong,  compact,  durable,  safe  and  eco- 
nomical mechanism,  made  in  different  sizes,  and  now  in  use  in 
every  part  of  the  world  where  the  electric  light  is  used.  The 
essential  parts,  common  to  all  dynamos,  as  well  as  to  Mr. 
Edison's,  are: 

1.  An  iron  body  constituting  the  magnetic  limbs,  or  field. 
This  is  always  wrapped  over  a  certain  portion  of  its  length 
with  insulated  copper  wire,  and  its  purpose  is  to  produce 


174  THOMAS  A.  EDISON 

between  its  ends  or  polar  surfaces,  a  region  or  field  of  mag. 
netic  force. 

2.  An  armature,  which  consists  of  a  series  of  coils  of  copper 
wire,  generally  wound  upon  a  subdivided  mass  of  iron,  and 
capable  of  revolution  about  an  axis  in  such  a  way  as  to  make 
each  coil  pass  successively  before  the  polar  surfaces  of  the 
magnetic  limbs.      This  is  always  so  placed  that  it  helps,  with 
the  magnets,  to  form  a  nearly  closed  magnetic  circuit  of  iron. 

3.  A  commutator,  which  is  merely  the  ends  of  the  armature 
coils   brought  to   one   side,  and   which,  revolving  with  the 
armature,  effects  a  change  in  the  direction  of  the  currents 
formed  alternately  plus  and  minus. 

4.  Several  brushes,  or  collectors,  usually  two  in  number, 
consisting  of  pieces  of  metal  which  press  upon  the  segments 
of  the  commutator,  and  which  are  in  metallic  communication 
with  the  terminals  of  the  machine. 

In  general,  the  armature  revolves  between  the  poles  of  the 
electro-magnet;  but  in  some  machines,  notably  those  intended 
to  furnish  alternate  currents,  the  armature  is  stationary,  and 
the  magnet  coils,  themselves,  revolve. 

The  wonderful  light-generating  dynamo  and  apparatus 
constructed  by  Mr.  Edison,  when  complete  and  in  operation, 
consists  of  a  regulating  box,  armature,  commutator,  brush, 
armature  revolving  from  left  to  right,  armature  revolving 
from  right  to  left,  brush  holder,  brush-holder  with  attach- 
ment to  rocker  arm,  babbitt  shell  for  journal,  safety  cut-out, 
safety  plug  for  cut-out,  switch,  lamp,  and  lamp  attached  to 
key  socket. 

The  field  magnets  of  the  new  Edison  Dynamo  consist  of 
vertical  cylinders,  as  shown  in  the  engraving,  with  large 
wrought  iron  cores,  resting  on  massive  cast-iron  pole  pieces 
which  nearly  enclose  the  armature.  The  extreme  length  of 
core  found  in  the  older  styles  have  been  reduced,  and  the 
diameter  correspondingly  increased,  so  as  to  preserve  the 


AND  HIS  INVENTIONS.  175 

massiveness,  a  feature  which,  in  both  cores  and  pole  pieces, 
it  is  claimed,  increases  the  magnetic  intensity  of  the  field 
and  lessens  the  liability 


Edison  Dynamo  in  Operation. 

The  armature  is   drum- shaped.     Its    core  consists   of  a 
number  of  sheet  iron  discs,  insulated  from  each  other  by 


176  THOMAS  A.  EDISOZT 

tissue  paper,  and  mounted  on  an  iron  shaft,  but  insulated 
from  it  by  an  interior  cylinder  of  lignum  vitce,  while  an  ex- 
ternal covering  insulates  it  from  the  coils.  These  consist  of 
cotton-covered  copper  wire  stretched  longitudinally,  and 
grouped  together  in  parallel,  twelve  wires,  more  or  less,  in  a 
group;  all  the  groups  being  so  connected  as  to  form  a  con- 
tinuous closed  circuit.  These  groups  are  arranged  in  concen- 
tric, and  are  of  the  same  number  as  the  segments  of  the 
commutator,  the  ends  of  the  wires  in  each  group  being  at- 
tached to  arms  connecting  with  the  commutator  segments;  a 
spiral  arrangement  being  adopted  in  making  the  connections 
between  the  straight  portions  of  the  wire  and  the  arms.  The 
object  of  grouping  is  to  secure  flexibility  for  winding  by  the 
use  of  small  wire,  and  low  electric  resistance  by  having  sev- 
eral wires  in  parallel,  the  effect  as  to  resistance  being  prac- 
tically the  same  as  if  the  several  wires  were  combined  in 
one.  At  the  ends  the  wires  are  insulated  from  the  core  by 
discs  of  vulcanized  fibre,  with  projecting  teeth.  The  discs  of 
the  core  are  bolted  together  by  insulated  rods,  and  the  coils 
are  confined  by  brass  bands  surrounding  the  armature.  The 
bar  armature,  formerly  used  in  the  Edison  Dynamo,  has  been 
abandoned. 

The  brushes  are  composed  of  several  layers  of  copper 
wires  combined  with  flat  copper  strips,  two  layers  of  wire 
being  placed  between  each  two  strips,  an  arrangement  which 
is  claimed  to  give  a  very  perfect  connection,  and  to  prevent 
sparking  by  furnishing  numerous  points  of  contact,  the 
copper  strips  confining  the  wire,  and  making  the  brush  more 
compact. 

HOW    TO    PUT    THE    DYNAMO    IN    OPERATION. 

To  put  the  dynamo  in  operation  we  first  fill  the  oil-cups 
and  set  the  feed,  then  start  the  armature  and  bring  it  to  full 
speed,  when  we  place  the  brushes  on  the  commutator.  We 
next  close  the  field-circuit  by  placing  the  plug  in  the  regula- 


AND  HIS  INVENTIONS.  177 

tor,  and  then  close  the  main  switch  on  the  dynamo.  As  soon 
as  the  current  is  developed  we  adjust  the  candle-power  of  the 
lamps  by  the  regulator  until  the  indicator  points  to  zero,  and 
also  adjust  the  brushes  to  prevent  any  sparking.  In  stopping 
the  dynamo,  we  follow  the  above  rules  in  their  reverse 
order. 

The  dynamo  should  always  run  with  no  sparks  at  the 
brushes,  and  should  be  kept  scrupulously  clean;  no  water 
should  be  allowed  near  the  machine,  nor  should  any  oil-cans, 
wrenches,  and  other  tools  be  left  near,  as  they  are  liable  to 
be  attracted  by  the  magnets  and  drawn  into  the  machinery. 
All  contact  surfaces  should  be  kept  bright  and  clean  and 
firmly  screwed  up. 

The  machine  should  carry  only  its  normal  load,  and  should 
never  be  overloaded.  "When  the  dynamo  is  in  operation  and 
the  load  is  increased  or  decreased  to  a  considerable  extent, 
the  brush-holder  yoke  will  sometimes  need  an  occasional 
adjustment  backward  or  forward  in  the  line  of  rotation,  in 
order  that  the  current  may  be  taken  off  at  the  point  of  high 
electro-motive  force,  at  which  point  there  is  no  sparking. 
This  point  often  varies  in  different  dynamos,  but  is  usually 
at  an  acute  angle  from  the  horizontal  diameter;  for  a  light 
load  it  will  be  on,  or  slightly  over,  the  line  of  horizontal 
diameter;  as  the  load  increases  it  will  travel  toward  the  line 
of  perpendicular  diameter. 

Switches  or  circuit-breakers  should  always  have  their 
contact  surfaces  clean,  and  must  make  firm  contact  when  the 
circuit  is  closed.  Safety  plugs  should  be  carefully  inspected, 
occasionally  cleaned,  and  firmly  screwed  in  place.  When  a 
safety-plug  requires  renewing  we  first  trip  the  switch  con- 
trolling its  circuit,  then  remove  the  old  plug,  replace  it  by 
the  new  one  of  the  proper  capacity,  and  then  turn  on  the 
current. 


THOMAS  A.  EDISON 


AND  HIS  INVENTIONS.  179 

GENERAL   INSTRUCTIONS    CONCERNING   THE  DYNAMO. 

The  machine  must  be  set  in  a  clean,  dry  place  on  a  firm 
foundation.  The  speed  must  be  constant  and  regular,  and  the 
belts  tight  and  free  from  slipping.  The  journal-bearings 
must  have  a  regular  and  constant  supply  of  good,  clean  and 
medium  heavy  lubricating  oil.  The  oil  should  be  filtered. 

The  bearing  at  commutator  end  will  generally  be  warmer 
than  at  tho  pully  end,  but  neither  bearing  should  feel  ex- 
ceedingly warm  to  the  hand.  If  too  hot,  loosen  the  cap  a 
little.  If  excessively  hot,  use  a  small  quantity  of  fine  plum- 
bago mixed  with  oil,  and  cool  off  with  cold  water  or  ice. 
When  the  machine  is  stopped,  remove  the  pillow  block,  and 
clean  and  scrape  the  bearing. 

The  commutator  must  always  present  a  clean,  polished 
surface  free  from  scratches.  If  accidentally  scratched,  the 
commutator  can  be  polished  with  very  fine  sandpaper, 
moistened  with  a  drop  of  oil.  Never  use  emery  paper  or 
cloth.  The  commutator  is  in  its  best  condition  when  it 
presents  a  rather  dark  glazed  surface.  The  commutator 
must  never  be  allowed  to  have  flat  spots;  always  keep  its 
circumference  perfectly  true.  Do  not  attempt  to  oil  or  fit 
while  running  with  current  on,  or  brushes  in  operation.  The 
brushes  must  always  be  firmly  fastened  in  the  holders,  and 
must  be  so  adjusted,  when  the  armature  is  not  running,  that 
they  rest  on  the  commutator  at  exactly  diametrically  opposite 
points;  the  bevel  end  of  the  brush  must  conform  accurately  to 
the  curve  of  the  cummutator.  The  brush-holder  should  be 
occasionally  moved  laterly  to  allow  brushes  to  wear  the  com- 
mutator evenly. 

The  pressure  of  the  brushes  on  the  commutator  must  be 
sufficient  to  keep  them  close  to  its  surface,  but  not  so  heavy 
as  to  cause  them  to  scour  or  cut  the  commutator. 

Do  not  let  the  brushes  become  saturated  with  oil.  They 
can  be  cleaned  by  washing  them  in  benzine.  The  brushes 


i8o  1HOMAS  A.  EDISON 

must  be  so  adjusted  in  the  holders  that  when  they  have  their 
correct  bearing  on  the  commutator,  the  thumb-screws  which 
govern  the  tension-spring  will  have  full  range  of  action. 
When  the  armature  is  at  rest,  the  brushes  should  be  lifted 
from  the  commutator,  and  held  away  by  the  small  clips  on 
the  brush-holder  provided  for  this  purpose. 

Strangers  witnessing  the  wonders  of  a  dynamo  in  motion 
should  be  exceedingly  careful  not  to  approach  too  near  the 
machine,  as  a  slip  or  fall  within  its  reach  might  occasion  in- 
stant death;  watches  also,  when  brought  too  near,  if  not  de- 
magnetized, are  apt  to  be  ruined.  It  should  be  said  in 
reference  to  the  Edison  system  of  electric  lighting,  and  to 
its  great  credit,  that  it  is  constructed  in  all  its  details,  with 
reference  not  only  to  the  best  possible  light,  but  also  to 
personal  safety  under  every  and  all  circumstances. 

When  Mr.  Edison  went  to  work  at  the  electric  dynamo, 
too  much  had  been  done  already  to  admit  of  his  doing  much 
pioneer  work.  His  great  mission  has  been  to  perfect,  and 
this,  too,  where  so  many  brilliant  and  burning  intellects  had 
been  directed  into  the  same  field.  His  labors  were  directed 
to  removing  from  the  dynamo  all  surplus  wire  not  useful  for 
purposes  of  generation ;  to  avoiding  unnecessary  internal 
resistance  in  the  machine,  and  the  consequent  excessive 
accumulation  of  heat,  etc.  In  a  word,  Edison's  share  in  per- 
fecting the  electric  light  process  involved  the  most  minute 
investigations  into  and  comparison  between  the  experiments 
of  all  preceding  inventors,  combined  with  a  genius  for  rapid 
invention  and  facile  advance  in  every  line  of  electric  skill, 
which  should  utilize  and  save  all  of  value  which  each  had 
done.  This  he  has  done  so  effectually,  that  the  very  words, 
"Electric  Light,"  must  stand  forever  as  closely  associated 
with  the  name  of  Edison  as  is  gravitation  with  Newton,  or 
the  telescope  with  Galileo. 


AND  HIS  INVENTIONS.  181 

ELECTRIC   MOTOR. 

"We  may  add  in  this  connection  that  an  electric  motor  is 
nothing  more  or  less,  virtually,  than  a  "  dynamo  reversed,'' 
where  the  electricity  is  brought  by  the  conducting  line  into 
the  magnetic  field  of  the  motor  and  causes  the  armature  to 
revolve,  and  thus  renders  the  electric  forces  available  for 
practical  purposes  in  running  machinery,  street  cars,  etc., 
etc.  A  stationary  dynamo,  run  by  steam  power,  generates  the 
electricity,  and  this  electricity  is  carried  by  the  conducting 
wire  to  the  electric  motor  on  the  street  car,  or  down  into 
a  mine,  or  wherever  it  is  wanted,  and  entering  the  motor, 
furnishes  the  requisite  power. 

The  modus  operand!  of  the  motor  has  been  described  as  a 
current  flowing  around  the  magnet,  and  instantly  the  near- 
est armature  section,  feeling  the  impulse  of  attraction,  will 
rush  forward  toward  the  point  of  contact.  But  directly  on 
its  approach  the  finger  reaches  a  non-conducting  section  and 
the  current  ceases.  The  deluded  armature,  no  longer  under 
the  influence  of  attraction,  flies  onward  impelled  by  its  own 
momentum,  and  allows  the  joke  to  be  played  on  the  next 
armature  section  coming  up  from  below.  As  soon  as  the 
connecting  finger  touches  another  conducting  section,  this 
second  armature  repeats  the  effort  of  its  predecessors  with 
equal,  but  with  no  better  success,  and,  after  failure,  relin- 
quishes the  field  for  the  next.  And  so  the  play  goes  on, 
until  the  wheel,  continually  gathering  momemjtum  from  mo- 
mentum, flies  like  the  revolving  saw,,  and  is  strong  enough 
to  turn  ponderous  machinery,  or  lifts  tons  upon  tons. 


i82  THOMAS  A.  EDISON 

Edison's  Pyre-Magnetic  Dynamo. 

A   MECHANISM    GENERATING  ELECTRIC    ENERGY  BY   HEAT   FROM 
A    STOVE. 

The  Edison  Pyro-Magnetic  Dynamo  is  designed  to 
produce  electric  energy  from  fuel,  and  may  be  used  in  con- 
nection with  the  wood  or  coal  heating  stoves  and  furnaces  that 
heat  our  d  wellings-  In  a  paper  prepared  by  Mr.  Edison  on  this 
new  invention  he  says  :  "  To  do  this,  has  long  occupied  the 
close  attention  of  inventors.  Could  the  enormous  energy 
latent  in  coal  be  made  to  appear  as  electric  energy  with 
reasonable  economy,  the  mechanical  methods  of  the  entire 
world  be  would  revolutionized,  and  another  grand  step  of  pro- 
gress would  be  taken. 

"Quite  recently  Lord  Rayleigh  concluded  that  from  a 
copper  iron  couple  a  conversion  of  not  more  than  one-three- 
hundredths  of  the  coal  energy  could  be  hoped.  As  a  heat 
engine,  therefore,  the  thermo  cell  can  have  no  higher 
efficiency  than  Carnot's  reversible  engine.  Another  line  of 
investigation  suggested  itself. 

"It  has  long  been  known  that  the  magnetism  of  metals 
has  been  markedly  affected  by  heat.  Nickel  loses  its  power 
of  being  magnetized  at  400°,  iron  at  a  cherry-red  heat,  and 
cobalt  at  a  white  heat.  Whenever  a  magnetic  field  varies 
its  strength  in  the  vicinity  of  a  conductor,  a  current  is 
generated  in  that  conductor;  so  it  occurred  to  the  inventor, 
that  by  placing  an  iron  core  in  a  magnetic  circuit,  and  by 
varying  the  magnetizability  of  that  core  by  varying  its 
temperature,  it  would  be  possible  to  generate  a  current  in 
a  coil  of  wire  surrounding  the  core.  This  idea  constitutes 
the  essential  features  of  the  new  generator,  which  therefore 
is  called  the  'Pyro-Magnetic  Generator  of  Electricity.' 

''The  principle  was  first  applied  to  the  construction  of  a 
simple  form  of  electric  engine,  a  pyro-magnetic  motor." 
This  consisted  of  a  permanent  magnet,  having  a  bundle  of 
small  tubes  made  of  thin  iron  placed  between  its  poles,  and 


Edison's  Pyro-Magnetic  Dynamo. 


1 84  THOMAS  A.  EDISON 

capable  of  rotation  about  an  axis  perpendicular  to  the  plane 
of  the  magnet.  By  suitable  means  hot  air  passes  through 
these  tubes,  so  as  to  raise  them  to  redness.  By  a  flat  screen 
placed  across  this  bundle  of  tubes,  and  covering  half  of 
them,  access  of  the  heated  air  tc  these  tubes  is  prevented. 
When  this  screen  is  so  adjusted  that  its  ends  are  equidistant 
from  the  two  legs  of  the  magnet,  the  bundle  of  tubes  will 
not  rotate,  since  the  cooler  and  magnetic  portions  beneath 
the  screen  will  be  equidistant  from  the  poles.  If  the 
screen  be  turned  about  the  axis  of  rotation,  so  that  one  of 
its  ends  is  nearer  one  of  the  poles,  and  the  other  nearer  the 
other,  then  rotation  of  the  bundle  will  ensue. 

"The  first  motor  constructed  on  this  principle  was  heated 
by  two  small  Bunsen  burners,  and  it  developed  about  700 
foot  pounds  a  minute.  A  second  and  larger  motor  is  now 
finished  which  will  weigh  about  1,500  pounds,  and  is  expected 
to  develop  about  three-horse  power.  In  both  these 
machines  electro-magnets  are  used  in  place  of  permanent 
magnets,  the  current  to  energize  them  being  derived  from 
an  external  source.  In  the  larger  machine  the  air  for  com- 
bustion is  forced  through  the  tubes  to  cool  them,  and  then 
is  forced  into  the  furnace  at  a  high  temperature. 

"The  construction  of  a  machine  of  sufficient  size  to  de- 
monstrate the  feasibility  of  producing  continuous  currents 
on  a  large  scale  was  at  once  begun  and  has  since  been  com- 
pleted. The  new  machine  consists  of  eight  elements,  each 
the  equivalent  of  the  device  already  described,  arranged 
radially  around  a  common  center.  The  machine  is  placed 
upon  the  top  of  anv  suitable  furnace,  fed  by  a  blast,  so 
that  the  products  of  combustion  are  forced  up  through  the 
armature  in  turn.  The  potential  difference  developed  by 
this  dynamo  depends  upon  the  number  of  turns  of  wire  on 
the  armature  coils,  the  temperature  difference  in  working, 
the  rate  of  temperature  variation,  and  the  proximity  of 
the  maximum  point  of  effect. 


AND  HIS  INVENTIONS.  185 

"  The  results  thus  far  obtained  lead  to  the  conclusion  that 
the  economy  of  the  production  of  electric  energy  from  fuel, 
by  the  pyro-magnetic  dynamo,  will  be  at  least  equal  to,  and 
probably  greater  than  any  of  the  methods  in  present  use. 
But  the  actual  output  of  the  dynamo  would  be  less  than  that 
of  an  ordinary  dynamo  of  the  same  weight.  Since,  however, 
the  new  dynamo  will  not  interfere  with  using  the  excess  of 
energy  of  the  coal  for  warming  the  house  itself,  and  since 
there  is  no  attendance  required  to  keep  it  running,  it  would 
seem  to  have  already  a  large  field  of  usefulness  for  it.  By 
using  the  regenerative  principle  in  connection  with  it  great 
improvement  may  be  made  in  its  capacity." 

EDISON  OK  STORAGE  BATTERIES. 

The  storage  battery,  says  Edison,  is  one  of  those  pecu- 
liar things  which  appeal  to  the  imagination,  and  no  more  per- 
fect thing  could  be  desired  by  stock  swindlers  than  thatvery 
selfsame  thing.  In  1879  I  took  up  that  question  and  devised 
a  system  of  placing  storage  batteries  in  houses  connected  to 
mains  and  charging  them  in  the  day  time,  to  be  discharged 
in  the  evening  and  nights  to  run  incandescent  lamps.  I  had 
the  thing  patented  in  18Y9,  but  there  is  nothing  in  it.  I 
rung  all  the  changes  on  it.  My  plates  were  prepared  like 
Plante's.  The  method  of  preparing  them  for  charging  is 
more  tedious,  but  it  is  better  than  that  of  Faure,  after 
preparation.  The  first  storage  battery  was  sent  from  France 
by  Faure  to  Sir  William  Thompson,  who  was  at  first 
astounded  by  it.  He  was  asked  to  endorse  it,  consented  and 
took  a  retainer;  but  on  investigation  he  became  convinced 
that  there  was  nothing  in  it,  and  returned  the  retainer  to  the 
French  Company.  The  more  he  investigated  the  more  he 
found  out  the  fallacy  of  the  whole  business. 

Scientifically  the  thing  is  all  right,  but  commercially  as 
absolute  a  failure  as  one  can  imagine.  You  can  store  it  and 
hold  it;  but  it  is  gradually  lost  and  will  all  go  in  time.  Its 


186  THOMAS  A.  EDISON 

efficiency,  after  a  certain  number  of  charges  hare  been 
sustained,  begins  to  diminish,  and  its  capacity  and  efficiency 
both  diminish  after  a  certain  time  in  use,  necessitating  an 
increased  number  of  batteries  to  maintain  a  constant  out- 
put. 

There  is  a  natural  law  working  against  the  storage  battery  ? 
and  that  is,  that  finely  divided  lead  decomposes  water.  It  is 
said  that  when  Sir  "William  Thompson  had  his  attention  called 
to  this  fact  he  "threw  up  the  sponge."  All  metals  are  fuel. 
"When  oxidized  they  are  ashes,  and  it  takes  energy  to  put 
them  back  again  into  metalic  form,  when  it  is  again  fuel. 

The  Edison  Municipal  Lamp. 

AN   INCANDESCENT   LIGHT   FOB   OUTSIDE   ILLUMINATION. 

The  Municipal  Lamp  is  an  incandescent  light  designed  for 
outside  lighting,  on  streets,  alleys,  courts,  in  mines,  caves,  and 
for  small  towns  or  suburban  districts,  etc.  It  is  also  equally 
as  well  adapted  for  lighting  railroad  yards,  platforms, 
tunnels  and  bridges.  The  lamps  are  placed  on  wires,  some- 
what similar  to  the  arc  lights,  and  are  operated  from  a  cen- 
tral station,  and  are  therefore  all  lighted  at  the  same  moment, 
or  extinguished. 

The  Municipal  Lamp  is  of  low  resistance,  with  thick  sub- 
stantial carbon,  the  length  of  the  loop  determining  the  candle- 
power  and  the  E.  M.  F.  required.  Hence  as  a  15-candle  lamp 
has  a  carbon  of  the  same  cross-section  as  one  of  50  candles, 
it  requires  the  same  current,  the  difference  being  simply  in 
the  volts  absorbed.  This  gives  a  remarkable  flexibility  to  the 
system,  the  only  requisite  in  calculation  being  that  the  total 
candle-power  in  each  of  the  various  circuits  shall  conform 
approximately  to  a  given  standard,  which  standard  is  found 
by  a  determination  of  the  most  economical  percentage  of  loss 
in  the  conductor  in  each  particular  instance. 


AND  SIS  INVENTIONS. 


Tba  Edison  Municipal  Incandescent  Lamp. 


1 88  THOMAS  A.  EDISON 

The  lamps  thus  far  used  have  required  about  three 
amperes,  and  have  been  of  the  same  standard  of  efficiency 
as  the  high  resistance  lamps  used  in  the  three-wire  system. 
Their  life  has  been  very  long,  reaching  in  multitudes  of 
cases  from  1,500  to  3,000  hours,  with  only  slight  blackening 
of  the  bulb  before  breaking,  The  standard  of  distribution 
for  this  lamp  has  been,  640  candles  for  each  circuit. 

A  second  type  is  made,  allowing  of  a  greater  number  on  a 
wire,  the  current  being  four  amperes,  an  increase  of  one-third, 
while  the  pressure  per  lamp  is  reduced  somewhat  in  excess 
of  that  proportion,  thus  raising  the  standard  of  efficiency,  and 
securing  1,000  candles  on  each  circuit  of  1,000  volts.  This 
effects  a  considerable  reduction  in  costs  of  conductors  and 
station  appliances  in  a  large  system,  and  also  reduces  the  per- 
centage of  change  in  current  when  a  lamp  breaks. 

It  gives  a  clean,  clear,  steady  and  brilliant  light.  Lamps  of 
various  degrees  of  candle-power  may  be  used  on  the  same 
circuit  to  meet  the  varying  requirements  of  locality,  and 
should  any  lamp  in  the  circuit  be  broken,  it  is  so  arranged 
that  the  other  lamps  continue  to  illuminate,  and  notice  of  the 
broken  lamp  is  instantly  given  at  the  central  station. 

The  standard  street  hood  adopted  for  the  Municipal,  after 
a  great  number  of  experiments,  has  a  metallic  frame  and 
top,  with  an  inverted  conical  reflector  of  opal  glass,  which 
"lights  up"  in  a  very  efficient  manner.  It  contains  a  socket 
and  cut-out  of  exceedingly  simple  construction,  which,  in 
case  the  safety  device  in  the  lamp  itself  should  fail,  operates 
to  complete  a  shunt  around  the  terminals,  and  also  to  main- 
tain the  continuity  of  the  circuit  when  a  lamp  is  removed, 
either  intentionally  or  by  accident.  The  method  of  re-ad- 
justment when  a  new  lamp  is  placed  is  such  as  to  compel  an 
inspection  of  the  mechanism  to  insure  continued  reliability. 

An  ornamental  form  of  hood  is  made  entirely  of  opal 
shades,  and  is  well  adapted  to  hotel  piazzas,  railroad 
approaches,  private  grounds  and  other  special  locations. 


AND  HIS  INVENTIONS.  189 

An  exceedingly  important  attachment  to  every  Municipal 
hood  when  suspended  from  either  an  iron  or  wooden  post  or 
other  support  in  the  open  air,  is  an  insulator  which  makes 
it  impossible  for  the  wires,  cross-arm  or  frame  of  the  hood 
to  become  grounded  at  this  point.  The  standard  form  con- 
tains a  hard-rubber  device,  which,  with  a  metallic  coupling  in 
which  it  is  encased,  makes  a  "double  petticoat"  insulator, 
capable  of  standing  any  mechanical  strain  which  may  be  put 
upon  it  in  practice. 

When  used  apart  from  the  ordinary  street  connection,  a 
special  socket  with  non-conducting  shell  is  supplied,  which 
also  serves  as  a  perfect  cut-out  for  every  lamp.  A  special 
flexible  cord  is  necessary  in  using  this  system,  which,  as  a 
matter  of  convenience  and  special  precaution  against  acci- 
dent, is  connected  at  the  ceiling  with  a  simple  and  orna- 
mental receptacle. 

The  station  apparatus  necessary  to  operate  each  circuit  is 
placed  on  a  separate  base,  and  a  number  of  these  sections, 
ranged  on  proper  supports,  allowing  of  free  access  from  the 
rear,  form  a  compact  switch-board,  preventing  liability  of 
leakage,  and  rendering  it  easy  to  connect  each  circuit  with 
any  one  of  several  dynamos. 

EDISON'S  NEW  CUT-OUT. AN  INGENIOUS  MECHANISM  TO  PREVENT 

A  LONG  LINE  OF  LAMPS  FROM  BECOMING  SUDDENLY 
EXTINGUISHED. 

In  the  Edison  Municipal  System  of  incandescent  lighting, 
incandescent  lamps  of  low  resistance  are  placed  in  series  on 
long  circuits  and  fed  with  a  constant  current  from  dynamos 
giving  an  E.  M.  F.  as  high  as  1,200  volts.  With  the  incandes- 
cent lamps  in  series  it  is  evidently  necessary  to  provide  a  means 
by  which  the  circuit  is  maintained  continuous  in  the  case  of 
a  lamp  giving  out,  and  various  automatic  cut-outs  have  been 
designed  for  this  purpose.  After  experimenting  for  a  long 
time  for  the  purpose  of  obtaining  a  device  which  should  be 


190  THOMAS  A.  EDISON" 

absolutely  certain  in  its  action,  Mr.  Edison  at  last  hit  upon 
a  very  simple  and  ingenious  arrangement  which  is  embodied 
entirely  with  the  lamp  so  that  no  external  cut-out  is  required. 
The  new  Municipal  Lamp  as  now  constructed,  has  a 
platinum  wire  extending  upwards  a  short  distance  between 
the  two  sides  of  the  carbon  horse-shoe.  This  third  wire 
passes  down  through  the  stem  of  the  lamp  outside  of  the 
vacuum,  and  is  joined  to  fine  iron  wire  holding  a  spring  in 
tension.  When  the  lamp  breaks  an  arc  is  formed  at  the 
positive  end  of  the  carbon,  and  the  current  divides  between 
the  negative  terminal  and  the  central  wire,  the  arc  being 
attracted  by  the  pointed  end.  The  current  thus  diverted  is 
sufficient  to  melt  instantly  the  iron  wire,  thus  liberating  the 
spring  under  tension,  which  forces  down  a  plug  that  short 
circuits  the  lamp,  and  extinguishes  the  arc.  This  novel  form 
of  cut-out  is  perfect  in  its  operation  and  avoids  all  the 
difficulties  encountered  in  the  older  forms. 

THE   EDISON   ELECTRIC    LIGHT    PLAXT   IN    THE    KOOKEEY  BUILD- 
ING  IN    CHICAGO,    ONE    OF    THE    LARGEST  ISOLATED 
PLANTS    IN    THE    WORLD. 

The  new  Rookery  Building  in  Chicago,  which  is  eleven 
stories  in  height,  and  is  considered  the  largest  and  finest 
office  building  in  the  world,  is  lighted  by  the  Edison  system. 
The  plant  is  said  to  be  one  of  the  largest  in  the  country,  and 
consists  of  four  No.  20  Edison  Dynamos,  each  having  the 
capacity  to  operate  800,  16-candle  lamps,  or  a  total  capacity 
of  3,200,  16-candle  lamps.  The  building  is  wired  for  4,000, 
16-candle  lamps.  All  the  wiring  of  the  building  is  concealed 
and  has  water-proof  insulation.  The  dynamos  are  operated 
from  a  counter-shaft  which  can  be  driven  from  either  one  of 
two  engines,  of  which  one  is  of  50,  and  the  other  250  horse 
power  capacity.  The  engines  are  of  the  Hamilton  Corliss 
type.  The  insulation  of  the  wires  of  the  building 


AND  HIS  INVENTIONS. 


I92 


THOMAS  A.  EDISON 


is   very  high,  each  circuit  having  passed  an  inspection    re- 
quiring an  insulating  resistance  of  one  megohm. 

The  arrangement  of  the  system  of  conductors  is  such  that 
tlje  variation  of  pressure  does  not  exceed  one  half  of  one  per 
cent  throughout  the  entire  building,  which  is  wired  on  the 
two-wire  system.  An  amperemeter  is  placed  in  circuit  with 
each  dynamo  to  show  the  amount  of  current  it  is  supplying. 
The  machine  wires  lead  to  a  set  of  omnibus  bars,  from  which 
are  laid  four  feeders,  upon  each  of  which  is  placed  an 
amperemeter  to  show  the  amount  of  current  being  delivered 
by  that  feeder  to  the  system. 

The  device  for  placing  different  dynamos  in  circuit  is 
very  complete,  it  being  impossible  to  notice  any  effect  what- 
ever upon  the  light  or  any  of  the  instruments,  or  in  the  op- 
eration of  the  dynamos,  where  a  machine  is  added  to,  or  taken 
away  from,  the  system.  The  new  Edison  lamps  of  110  volts 
are  used  throughout  the  building,  requiring  .46  of  an  ampere 
for  a  16-candle  lamp.  The  cut-outs  in  the  building  are  all 
made  of  porcelain;  and  are  grouped  at  four  different  points 
on  each  floor  in  handsome  cabinets  built  for  the  purpose, 
which  are  set  in  the  walls,  so  that  they  are  not  in  any  way 
conspicuous.  The  court  is  lighted  by  several  groups  or 

lamps,  con- 
from  ten 


bunches  of 
sisting  o  f 
to  thirty 
group,  the 
ing  of  a 
design, 
large  and 
electric 
installed 
Leon  ard 
of  Chicago. 


lights  in  a 
fixtures  be- 
handsome 
This  very 
successful 
plant  was 
by  Messrs. 
and  Izard 


Amperemeters  and  Regulator  Boxes, 


AND  HIS  INVENTIONS.  193 

Edison's  High  Economy  Converter  System. 

Mr.  Edison  says  of  this:  "In  systems  wherein  a  number 
of  converters  are  used,  the  difficulty  arises  that,  although  the 
whole  or  the  greater  number  of  the  lamps  supplied  are  in 
circuit  and  using  current  only  during  about  four  hours  out  of 
twenty-four,  the  converters  themselves  are  using  current 
during  the  whole  day.  There  is  a  loss  of  from  seven  to 
twelve  per  cent.,  according  to  the  construction  in  each  con- 
verter, and  this  loss  goes  on  all  the  time,  whether  all  the 
lamps  are  in  circuit  or  only  a  very  few  of  them,  so  that  the 
removal  of  lamps  does  not  cause  a  corresponding  reduction 
in  the  amount  of  current  required  in  the  system.  It  will  be 
seen  that  this  detracts  enormously  from  the  economy  of  the 
system,  since,  though  only  a  few  lamps  may  be  in  use,  it  is 
necessary  to  always  keep  the  generation  of  current  at  a 
sufficient  amount  to  supply  the  loss  in  all  the  converters.  In 
some  cases  the  current  used  in  the  converters — which  of 
course  is  a  dead  loss  to  those  operating  the  plant — will  be 
equal  in  amount  to  that  sold  to  the  consumers.  Evidently 
this  results  in  a  great  diminuition  of  the  profits  of  the 
business. 

"I  propose  to  remedy  this  by  so  arranging  the  system  that 
only  so  many  converters  will  be  in  circuit  at  any  time,  as  are 
required  to  supply  the  lamps  or  translating  devices  actually 
in  use,  providing  the  converters,  or  certain  of  them,  with 
switches,  whereby  their  primary  and  secondary  circuits  may 
be  opened  or  closed,  as  desired,  and  thus  any  desired  num- 
ber of  the  converters  may  be  removed  from,  or  maintained 
in  connection  with,  the  system,  according  to  the  amount  of 
current  required  to  be  used  at  any  time.  I  prefer  to  employ 
switches  controlled  from  the  central  station,  whereby  any 
particular  switch  may  be  operated  without  affecting  the 
others,  though  they  are  all  controlled  by  the  same  circuit." 


1 94  THOMAS  A.  EDISON 

The  Incandescent  House  Lamp. 

There  are  in  fact  only  two  kinds  of  elec- 
tric light :  one  known  as  the  arc  light  and 
the  other  as  the  incandescent.  The  arc 
light  is  produced  by  an  intense  current  of 
electricity  through  two  separate  carbon 
points.  At  the  points  where  the  two  car- 
bon rods  come  together  the  current  of  elec- 
tricity passes  from  one  point  to  the  other 
and  produces  an  arc,  which  might  be  called 
"pure  lightning,"  and  which  consumes  the 
carbons.  This  makes  the  intense  light 
which  dazzles  the  eye,  and  by  the  light  of 
which  a  photograph  may  be  taken-  Davy 
produced  the  arc  light  in  1810,  using  char- 
coal inclosed  in  a  vacuum.  Foucault  fol- 
lowed in  1844,  using  carbon  from  the 
retorts  of  gasworks,  which  is  much  harder 
and  less  easily  consumed.  As  early  as 

The  Edison  Honse  ,       -.-,•,  -,      •,      .-,  j       T»     • 

Lamp.  1844-45  the  Place  de  la  Concorde,  Pans, 

was  lighted  by  an  arc  light  fitted  up  by  Delenil.  In  1858 
Jobart  proposed  to  make  use  of  small  carbon  in  a  vacuum, 
and  in  the  same  year  F,  Moleyns,  of  Cheltenham,  patented 
his  lamp,  and  in  1859  Dumoncel  experimented  with  carbon 
filaments  of  cork,  sheepskin,  etc. 

The  incandescent  light  is  produced,  by  a  current  of  elec- 
tricity passing  through  a  filament  of  carbon,  in  a  vacuum, 
and  the  carbon  is  heated  to  a  white  heat  which  gives  out 
the  light.  These  carbon  filaments  will  endure  for  months, 
but  in  fact,  they  are  slowly  consumed,  and  like  the  arc  lights, 
are  replenished. 

Edison's  first  incandescent  light  was  made  by  using  fine 
platinum  wire.  He  now  uses  bamboo  fibre,  which  is  first  by 
machinery  divided  into  fibres  of  about  one  millimeter  in 
diameter  and  twelve  centimeters  in  length. 


AND  HIS  INVENTIONS. 


I 

196  THOMAS  A.  EDISON 

Edison  Building,  Chicago. 

LOCATION  OF  THE  EDISON  ELECTEIC  LIGHT   PLANT. 

The  electrical  plant  in  the  Edison  Building,  Chicago,  on 
Adams,  near  LaSalle  Street,  was  planned  and  supervised  by 
W.  S.  Andrews,  who  has  made  it  as  perfect  as  the  present 
stage  of  this  business  will  admit.  It  is  known  as  the 
"  Central  Station."  The  full  capacity  is  thirty-six  dynamos, 
which  can  operate  about  50,000  lamps  of  sixteen  candle- 
power  each,  aggregating  800,000  candles.  The  electric 
current  was  turned  on  the  underground  conductors,  August 
6,  1888,  and  thousands  of  bright  lights  in  the  many  stores, 
offices  and  other  places,  attest  its  great  success. 

The  ground  floor  is  devoted  to  the  company's  offices,  store- 
rooms, and  a  very  capacious  boiler  and  engine  department. 
The  second  floor  contains  the  dynamos,  located  over  the 
engine  room,  additional  boilers,  and  the  motors,  situated 
over  the  offices.  On  the  west  side  of  this  floor  are  the  feeder 
equalizers,  ampere-meters,  pressure  indicators,  safety-catches 
and  main  conductors,  all  of  which  occupy  the  entire  length 
of  the  room,  103  feet.  The  Chicago  Edison  Company  sell 
electricity  to  the  public  through  the  meter,  so  that  each  con- 
sumer pays  only  for  what  he  actually  uses.  This  electricity 
may  also  be  used  for  power,  as  well  as  light.  In  this  way 
great  steam-engines,  representing  almost  unlimited  ability, 
generate,  by  the  aid  of  the  dynamos  in  a  local  plant,  a 
prodigious  volume  of  electricity,  which,  through  underground 
conductors,  becomes,  for  miles  in  every  direction,  available 
for  illumination  and  power. 

Thus  has  Mr.  Edison  demonstrated  his  assertions  made 
four  years  ago  under  the  caption  "The  Commercial 
Evolution  of  Electricity,"  and  which  excited  much  criticism 
at  the  time,  that '-'  Two  years'  experience  proves,  beyond  a 
doubt,  that  the  electric  light,  for  household  purposes,  can  be 
produced  and  sold  in  competition  with  gas." 


AND  HIS  INVENTIONS. 


197 


198  THOMAS  A.  EDISON 

Edison's  Ground  Detector  For  Electric 
Light  Circuits. 

A    MECHANISM    FOB    LOCATING    THE     "BREAK"    IX    AN    UNDER- 
GROUND    WIRE. 

The  object  of  this  mechanism  is  to  determine  the  exact 
location  of  any  defect  or  break  in  an  underground  wire, 
carrying  or  intended  to  carry  an  electric  current.  The  diffi- 
culty of  locating  the  position  of  a  "ground"  in  electric  light 
circuits  varies  directly,  other  things  being  equal,  with  the 
weight  or  cross-section  of  the  main.  In  other  words,  an 
error  in  the  determination,  which  would  represent  a  dis- 
placement of  the  "ground"  from  the  true  position  to 
the  extent  of  10  feet  in  mains  whose  sectional  area  is  5,000 
circular  mils,  would,  under  similar  circumstances,  induce 
an  error  of  200  feet  in  mains  of  100,000  circular  mils  cross 
section.  It  consequently  follows  that  in  most  cases  of 
grounds  in  mains  of  considerable  size  the  location  of  the 
fault  cannot  be  carried  out  practically  to  anything  ap- 
proaching the  degree  of  accuracy  that  it  would  be  desirous 
to  attain. 

Thus  while  a  localization  to  the  limit  of  one  hundredth  of 
an  ohm  accuracy  generally  requires  considerable  time,  care, 
experience  and  calculation,  such  an  error  would  involve  a 
displacement  of  100  feet  in  mains  of  100,000,  and  of  200 
feet  in  mains  of  200,000  circular  mils  section.  The  con- 
sequence is  that  in  all  such  cases  the  slow  process  of  digging 
and  disconnection  has  to  be  resorted  to,  first  by  ascertaining 
between  which  pair  of  safety  catch  boxes  the  ground  lies, 
then  by  sinking  a  hole  in  that  half-section,  next  in  the 
quarter-section,  and  so  on  until  the  final  tube  is  arrived  at. 
Much  time  and  labor  would,  therefore,  be  saved  if  some 
practical  method  could  be  devised  of  detecting  directly  from 
the  surface-level  the  position  of  the  fault  in  the  wire.  The 
telephone  has  been  tried,  and  is  still  sometimes  employed  in 


AND  HIS  INVENTIONS. 


199 


connection  with  an  induction  coil  carried  over  the  pipe  line 
while  the  current  from  a  few  cells  of  battery  is  passed 
through  the  mains  of  that  section;  but  the  success  at- 
tained by  this  method  has  not  been  very  great,  partly  from 
the  great  delicacy  of  the  telephone,  which  is  liable  to  con- 


Edison's  Ground  Detector  for  Electric  Light  Circuits, 
fusingly  pick  up  and  mingle  induction  currents  from   other 
neighbor-ing  conductors,  and  partly  from  other  causes. 

With  the  object  of  solving  the  problem  more  satisfactorily, 
Mr.  Edison  instituted  at  his  laboratory,  experiments  which 
have  resulted  in  the  use  of  a  device  which  materially 


200  THOMAS  A.  EDISON 

economizes  the  time  and  labor  expended  in  the  subdividing 
sectional  process.  The  principal  employed  has  been  nothing 
more  than  the  deflection  of  an  ordinary  magnetic  needle  by 
the  magnetic  force  of  a  current  passing  beneath  it.  The 
extent  to  which  this  principle  can  be  adopted — that  is  to 
say,  the  limit  of  the  ground  resistance,  which  can,  under 
ordinary  circumstances,  be  so  detected  from  the  street  above, 
is  easily  capable  of  estimation. 

Experiment  seems  to  show  that  the  iron  pipe  enclosing  the 
main  does  not  reduce  the  deflection  produced  by  the  current 
to  any  serious  extent.  Consequently  it  might  be  expected 
if  a  compass  needle  were  carried  above  the  surface  over  the 
mains  and  a  periodic  current  of  seven  or  more  amperes 
were  sent  regularly  through  the  grounded  main,  free  at  the 
distant  end,  then  the  deflection  of  the  needle  from  its 
position  of  rest  (under  weak  artificial  control)  parallel  to  the 
pipes,  would  serve  to  indicate  that  the  ground  was  still 
ahead  of  the  observer;  while  the  cessation  of  the  current 
would  indicate  that  the  ground  had  been  passed  and  that 
the  current  had  left  the  main. 

Mr.  Edison's  instrument  for  thus  detecting  the  location  of 
the  fault,  and  which  he  calls  his  "Ground  Detector," con- 
sists of  a  compass  box  swung  on  gimbals  containing  two 
light,  strongly  magnetized  needles,  m  1,  m  2,  m  3,  m  4,  as 
shown  in  the  figure,  rigidly  connected  by  a  thin  aluminium 
strip  that  also  serves  as  a  pointer  over  a  graduated  dial.  By 
this  means  the  moment  of  inertia  of  the  needles  and  pointer 
is  small  and  its  movements  are  quick.  The  whole  is  clamped 
at  the  lower  end  of  a  stick  held  in  the  hand.  A  small  con- 
trolling magnet  to  bring  the  needle  parallel  to  the  line  of 
tubes  has  generally  to  be  carried  on  a  clamp  above  the  needle 
or  laid  on  the  ground  near  to  it. 


AND  HIS  INVENTIONS,  201 

Edison's  Method  of   Regulating  the 
Current. 

In  regulating  the  current  of  electricity  that  goes  out  from 
a  generating  station  to  light  up  this  or  that  street,  block, 
etc.,  Mr.  Edison's  method  consists  in  interposing  in  the 
shunt  circuit,  in  which  the  field  magnets  are  placed,  an 
adjustable  resistance.  When  the  number  of  lamps  in  the 
circuit  is  increased,  resistance  is  thrown  out  of  the  field 
circuit.  Similarly,  when  the  speed  increases,  resistance  is 
thrown  into  the  field  circuit,  and  taken  out  when  this 
diminishes.  The  electro  motive  force  can  thus  be  kept 
practically  constant,  whatever  the  changes  may  be  in  the 
working  circuit.  At  central  stations,  the  shifting  of  these 
resistances  is  done  by  hand,  but  their  manipulation  is  effected 
automatically  in  separate  plants  of  moderate  size,  such  as 
those  designed  for  lighting  workshops,  large  buildings,  etc. 
The  difficulties  of  an  automatic  regulation  of  very  large 
plants,  such  as  those  operated  from  a  central  station,  are  con- 
siderable, and  Mr.  Edison  has  always  preferred  to  have  a 
mode  of  regulation  as  free  as  possible  from  mishaps. 

This  field  resistance  is  varied  in  accordance  with  the  in- 
dications of  a  galvanometer  placed  in  a  Wheatstone  bridge. 
An  incandescent  lamp  is  placed  on  one  side  of  the  bridge  and 
the  variable  resistance  of  the  bridge  adjusted  so  that  the 
galvanometer  t  needle  stands  at  zero,  when  the  lamp  is 
giving  its  natural  light.  As  the  resistance  of  the  incandes- 
cent carbon  filament  varies  with  its  temperature,  any  change 
in  the  current  following  through  the  lamps,  will  immediately 
destroy  the  balance  of  the  bridge  and  cause  [the  needle  to 
move  in-  one  direction  or  the  other,  according  as  the  lamp 
rises  or  falls  in  candle-power.  Resistance  is  then  introduced 
into,  or  thrown  out  of  the  field  circuit  until  the  needle  returns 
to  its  natural  position.  These  resistances,  which  consist  of 


202  THOMAS  A.  EDISON 

coils  of  German-silver  wire,  are  readily  manipulated  by  the 
attendant  by  means  of  a  switch. 

It  might  be  supposed  that  this  duty  on  the  part  of  the 
attendant  would  require  constant  watchfulness,  but  this  is  far 
from  being  the  case. 

In  any  extensive  distribution  of  the  electric  light,  the 
variation  in  the  demand  for  current  is  a  calculable  one,  and  the 
greater  the  number  of  consumers,  the  more  easily  the  amount 
and  time  of  these  variations  can  be  foreseen. 


The  Edison  Meters. 

The  Edison  Meter  has  two  cells,  the  indications  of  one 
serving  as  a  check  upon  the  other,  in  both  of  which  are 
zincs,  which  are  in  the  circuit,  and,  consequently,  gradually 
consumed.  Only  a  fraction  of  the  current  passes  through, 
and  the  consumption  of  the  zinc  is  small.  These  plates  are 
weighed  statedly,  and  from  this  weight  the  amount  of 
electricity  consumed  is  reckoned.  As  the  resistance  of  the 
cell  varies  with  its  temperature,  it  is  kept  constant  by  a  lamp 
automatically  lit  or  extinguished,  as  the  temperature  falls  or 
rises.  This  is  done  by  an  expansion  bar  closing  and  breaking 
the  circuit  of  the  lamp. 

In  Edison's  automatic  registering  meter,  there  are  two 
cells  placed  side  by  side,  constructed  so  that  the  cell  itself 
forms  one  plate,  the  other  being  hung  in  the  liquid  from  the 
same  scale  beam.  The  electrical  connections  are  so  that  the 
current  goes  from  the  plate  forming  the  jar  to  that  suspended 
plate,  which  is  raised  in  one  cell,  and  from  the  lowered 
suspended  plate  to  the  enclosing  jar  in  the  other  cell.  The 
raised  plate  is  consequently  gaining  in  weight  and  the 
lowered,  losing.  When  the  raised  plate  becomes  the  heavier 
of  the  two,  it  descends,  and  the  current  is  reversed.  There  is, 
therefore,  a  successive  gain  and  loss  of  weight  by  the  sus- 


AND  HIS  INVENTION'S.  203 

pended  plates,  which  causes  the  scale  beam  to  periodically 
oscillate,  each  movement  of  which  acts  upon  a  registering 
apparatus,  resembling  the  dial  of  a  gas-meter.  The  dial 
shows,  not  the  amount  of  electricity  in  electrical  measure, 
but  the  equivalent  of  the  amount  of  gas  necessary  to  give  the 
light  furnished. 


Edison  Junction    Box   and   Safety   Catch. 

In  large  cities  the  mains,  in  which  are  the  copper  insulated 
wires,  are  laid  about  two  feet  under  the  ground,  and  are 
arranged  so  that  they  form  a  net-work  throughout  the  whole 
district,  constituting,  in  fact,  a  gigantic  sieve,  of  which  the 
blocks  are  the  meshes,  and  these  are  joined  together  at  the 
corners  by  means  of  Junction  Boxes.  The  main  junction 
boxes  are  constructed  by  means  of  curved  metal  arms, 
adapted  for  expansion  and  contraction.  Similar,  though 
smaller,  boxes  serve  for  the  connection  of  house  conductors 
with  the  mains.  In  these  two  boxes  a  wire  is  interposed  in 
the  branch  circuit  which  constitutes  the  safety-catch,  and 
which  is  made  of  fusible  metal,  designed  to  cut  off  the 
current,  if  by  accident  it  should  become  too  strong  to  injure 
the  lamps,  or  to  cause,  in  the  conducting  wires,  a  danger- 
ous heating.  These  boxes  also  enable  the  circuit,  in  case  of 
accident,  to  be  interrupted  at  the  necessary  point,  so  as  to 
isolate  parts  of  the  circuit  that  may  be  inaccessible,  while 
the  remainder  is  still  supplied. 

The  interior  conductor  for  houses  is  made  of  copper 
wires  wrapped  in  a  casing  of  cotton  rendered  incombustible, 
and  if  desirable,  may  be  covered  with  silk.  In  the  path  of 
these  wires,  Mr.  Edison  also  places  little  safety-plates,  thus 
multiplying  his  usual  precautions  so  that  a  fire  is  not  possible 
through  any  irregularity  of  current. 


204 


THOMAS  A.  EDISON 
Train  Telegraphy. 


HOW   A   TELEGRAM   MAY   BE    SENT    OR   RECEIVED   FROM   A   RAP- 
IDLY   MOVING   TRAIN. 

The  system  of  telegraphing  on  the  train  while  in  rapid 


OPERATOR  RECEIVING  AND  SENDING  MESSAGES  ON  RAILWAY  TRAIN. 
motion,  having   a  telegraph  office  in  the  parlor  car,  and  all 


AND  HIS  INVENTIONS. 


205 


over  the  world,  is  due  to  Mr.  Edison.  In  the  first  equip- 
ment— on  the  Lehigh  Valley  Railroad — the  inductive 
receiver  on  the  car  consisted  of  a  coil  of  many  turns  of  wire 
wound  round  the  car,  and  the  line  conductor  was  an  insulated 
wire  laid  along  the  track.  While  this  system  left  little  to  be 
desired,  it  involved  some  expense  'which  is  avoided  by  the 
method  used  at  present. 

This  consists  in  the  employment  of  the  roof  of  the  car, 
where  such  is  available,  as  a  static  receiver,  and  the  line  is 
an  ordinary  wire  strung  upon  short  poles  near  the  track. 
The  roof  of  the  car,  by  the  present  system,  is  in  most  cases, 
available,  and  a  car  can  be  equipped  ready  for  work  in  a 
remarkably  short  time.  All  that  is  necessary  is  the  attach- 


Fia.  33.   SHOWING  SYSTEM  OF  TELEGBAPHY  FEOM  A  CAB  WHILE  THE  TRAIN  is  IN 
RAPID  MOTION. 

ment  of  a  wire  to  the  roof,  another  to  the  swivel  plate  of  a 
car  track  for  a  ground,  and  the  insertion  of  the  instruments 
in  the  circuits  thus  formed.  A  short  pole  telegraph  line 
extends  along  side  of  the  railroad  track  at  a  distance  of 
eight  or  ten  feet,  the  poles  being  much  smaller  than  the 
ordinary  telegraph  poles  and  from  ten  to  sixteen  feet  high. 
At  their  top  is  placed  an  ordinary  porcelain  insulator,  strung 
upon  which  is  a  single  galvanized  telegraph  wire.  Whenever 
practicable,  the  metal  roof  of  the  car  is  employed  as  the 


206  THOMAS  A.  EDISON 

inductive  receiver  of  the  car,  but  where  no  metal  roof  exists 
an  iron  or  brass  rod  or  tube,  half  an  inch  in  diameter,  is  em- 
ployed, placed  under  the  lines  of  the  car.  From  the  roof 
the  wire  passes  to  the  instruments,  and  then  to  the  wheels  of 
the  car. 

The  diagram,  Fig.  33,  shows  the  arrangement.  The  roof 
A  or  bar  B  are  connected  to  the  secondary  C  of  an  induction 
coil  The  primary  of  the  coil  is  connected  to  the  front  con- 
tacts of  the  double  pointed  key  D,  in  which  is  also  included 
thebattery  H,  and  a  buzzer  arrangement  opposite  the  core  of 
the  coil,  for  transmitting  a  series  of  impulses  to  the  line 
whenever  it  is  closed.  When  the  key  is  upon  the  front 
contact  also,  the  extra  contact  shown  at  the  top  of  the  key 
closes  the  secondary  circuit  and  allows  the  charges  to  be 
sent  into  the  roof.  When  the  key  is  on  its  back  con- 
tact, both  its  secondary  and  primary  coils  are  cut  out, 
the  charge  from  the  roof  passing  by  the  wire  directly 
to  the  key  and  thence  through  the  telephone  to  the 
earth." 

The  operator's  equipment  is  quite  simple,  and  consists 
merely  of  a  small  tablet  to  which  the  key,  the  coil  and  the 
buzzer  are  attached,  and  just  with  sufficient  top  surface  to 
hold  a  telegraph  blank  conveniently. 

The  battery  employed  is  enclosed  in  a  box  and  can  be 
placed  beside  the  operator,  if  it  is  desired.  The  oper- 
ator is  supported  by  head  gear  as  shown  in  figure.  A 
battery  of  twelve  small  cells  is  employed  in  circuit  with  the 
primary  of  the  induction  coil,  although  it  is  said  that  two 
cells  can  do  the  work.  The  primary  and  secondary  of  the 
induction  coil  are  respectively  about  35  and  250  ohms. 

The  arrangement  at  the  terminal  station,  so  far  as  the 
induction  circuits  and  instruments  are  concerned,  is  indenti- 
cal  with  that  on  the  car;  but  in  addition  there  is  supplied  a 


AND  HIS  INVENTIONS.  207 

Morse  arrangement  by  means  of  which  the  line  can  be  used 


OPERATOR'S  TRAIN  TELEGRAPHING  APPARATUS. 
for  the  transmission     of  ordinary    Morse    business.      The 


208  THOMAS  A.  EDISON' 

circuit  is  made  continuous  for  the  induction  system  by 
means  of  a  condenser  which  transmits  the  impulses  when 
the  Morse  key  is  open. 

On  a  trial  trip  on  the  Lehigh  Valley  Railroad  a  large 
number  of  messages  were  sent  and  received  without  the 
slightest  delay  of  any  kind.  One  of  the  striking  demonstra- 
tions of  the  wide  application  of  the  system  was  the  sending 
of  a  dispatch,  on  this  occasion,  from  the  rapidly  moving 
train,  to  John  Fender,  of  London,  England,  via  the  Atlantic 
Cable. 


The  Edison  Mimeograph. 

The  Mimeograph,  invented  and  carefully  perfected 
by  Mr.  Edison,  is  an  ingenious  apparatus  for 
duplicating,  or  manifolding  letters,  circulars,  etc.,  without 
any  trouble,  and  with  rapidity.  Three  thousand  copies 
may  be  made  from  one  writing  or  stencil,  no  previous 
practice  being  required.  The  manner  of  making  the  stencil 
or  first  writing  is  very  simple.  A  sheet  of  thin,  sensitive 
paper  is  laid  over  a  finely  grooved  steel  plate,  the  corrugations 
of  which  are  so  close  as  to  be  nearly  imperceptible.  The 
writing  on  the  stencil  sheet  is  done  with  a  smooth  steel  stylus, 
which  is  about  the  size  of  a  well-sharpened  lead  pencil. 
The  paper  is  perforated  from  the  under  side,  leaving  the 
stylus  free  to  roam  at  the  will  of  the  writer;  the  corrugation 
on  the  plate  affording  just  enough  resistance  to  the  stylus  to 
prevent  slipping  and  make  the  writing  easy  and  natural. 
After  the  stencil  is  completed  it  is  placed  in  a  suitable  frame 
and  copies  made  to  any  number  desired  by  passing  an  ink 
roller  over  the  surface — a  process  so  well-known  as  to  need 
no  further  explanation.  In  this  way  music,  sketching, 
mechanical  drawings,  maps,  architectural  drawings,  and  in 


AND  HIS  INVENTIONS.  209 

fact,  anything  that  can  be  done  with  a  lead  pencil,  can  be 
done  by  the  mimeograph  process. 


Edison's  Improved  Phonoplex. 

In  the  Edison  duplex  or  "Phonoplex "now  in  use,  the 
difficulties  of  duplexing  to  intermediate  or  way  stations  is 
overcome  by  adding  to  the  ordinary  Morse  instruments 
another  which  responds  to  rapid  induction  impulses,  such  as 
those  given  by  a  spark  or  induction  coil.  The  system  has 
been  still  further  improved  by  Mr.  Edison,  so  that  it  may 
now  be  used  as  a  triplex,  or  equivalent  to  three  independent 
circuits.  This  is  accomplished  by  adding  to  the  apparatus 
just  described,  a  second  form  of  induction  apparatus;  but 
instead  of  transmitting  and  receiving  Morse's  signals  by 
simple  induction  impulses  of  considerable  strength,  as  does 
the  simple  induction  apparatus,  this  third  apparatus  employs 
rapidly  occurring  induction  waves  or  vibrations  which  form 
a  musical  note,  this  note  being  transmitted  into  dots  and 
dashes  for  producing  Morse's  harmonic  signals,  and  thus  the 
"  Phonoplex  "  system  becomes  a  success. 


The  Sea  Telephone. 

HOW    SHIPS   MAY    TALK    ON   THE    OCEAN. 

Mr.  Edison,  who  has  expended  over  $2,000,000  in 
experiments,  is  wide-awake  to  the  possibility  of  inter-ship 
communication  at  sea.  His  experiments  on  this  device 
have  been  confined  mainly  on  the  waters  of  the  Caloosa- 
hatchie,  where  he  has  succeeded  in  conveying  intelligible 
messages  a  distance  of  one  mile.  The  principle  on  which  he 
will  endeavor  to  perfect  this  instrument  is  the  remarkable 
facility  afforded  by  water  for  the  transmission  of  sound. 
Divers  in  the  ocean  have  heard  the  swash  of  a  steamer's 


210 


THOMAS  A.  EDISON 


wheels  when  fifteen  miles  away,  and  Mr  Edison  believes  he 
can  transmit  his  messages  from  ship  to  ship  a  distance  of  at 
least  seven  miles. 

He  proposes,  after  he  has  perfected  his  apparatus,  to  have 
the    large    ocean   steamers   equipped  with   a  steam-whist*-* 


The  Sea. 

device,  worked  by  keys  somewhat  similar  to  a  telegraph 
instrument,  and  transmitters  after  the  telephone  fashion. 
Under  the  water-line  of  each  steamer  will  be  a  sounder  con- 
nected with  the  captain's  cabin  by  a  thin  transmitting  wire 
running  through  a  tube.  When  the  captain  of  one  vessel 


AND  HIS  INVENTIONS.  211 

wants  to  signal  another  he  will  sit  down  at  his  key-board, 
turn  the  steam  on  his  whistle,  manipulate  the  keys,  and 
send  his  message  out  into  the  waves  that  break  against  the 
sounder.  This  sound  will  pass  unbroken  from  wave  to  wave 
until  it  runs  up  against  the  sounder  of  any  vessel  that  may 
be  within  reach  of  the  volume  of  sound. 

As  soon  as  the  sound  waves  strike  the  sound  of  the 
hull  of  the  vessel  within  reach,  the  message  will  run  over 
the  electric  wire  to  the  captain's  cabin,  where  it  will  ring  an 
electric  bell.  An  attendant  will  then  take  down  the  message 
as  it  comes  from  the  water,  by  means  of  keys. 

After  the  message  has  been  received  the  captain  can  swing 
his  vessel  around  and  continue  the  message  through  seven 
mites  more  of  water  in  the  same  direction  until  it  strikes 
another  vessel,  when  the  operation  may  be  again  repeated 
until  the  breadth  of  the  ocean  space  has  been  crossed. 


212  THOMAS  A.  EDISON 

The  Edison  Bridge  for  Measuring  Magnetic 
Conductivity. 

"Perhaps  no  electric  measuring  instrument,"  says  Mr. 
Edison,  "  has  proved  more  useful  in  practice,  especially  if  we 
consider  the  various  forms  which  it  has  assumed,  than  the 
device  contrived  by  Christie,  and  commonly  known  as 
'  Wheatstone's  Bridge'.  It  was  with  a  belief  that  a  similar 
instrument  could  be  constructed  which  should  perform  the 
same  service  for  magnetic  measurements  that  the  experiments 
were  made,  the  results  of  which  I  have  the  honor  now  to 
present. 

"  The  "Wheatstone  Bridge  is  based  upon  the  fact  that  if  two 
points  of  different  electric  potentials  are  united  bv  two  con- 
ducting paths,  the  fall  of  potentials  along  these  paths  is 
absolutely  the  same,  provided,  that  these  paths  are  absolutely 
alike  electrically.  Consequently,  if  two  points  equidistant 
from  the  place  of  higher  potential  be  connected  together,  no 
current  will  flow  through  the  connecting  wire.  So  by 
analogy,  if  two  points  be  maintained  at  a  constant  difference 
of  magnetic  potential  the  fall  of  potentials  from  one  to  the 
other,  through  two  or  more  paths,  will  be  absolutely  uniform 
in  all,  provided  these  paths  be  magnetically  identical.  Hence, 
at  any  points  equidistant  from  a  given  terminal  the  magnetic 
potential  is  the  same,  and  these  points  could  be  without 
differential  action  upon  a  magnetic  pole. 

"The  magnetic  bridge  may  be  constructed  in  the  form  of  a 
rhomb,  the  typical  form  of  the  Wheatstone  Bridge.  For 
this  purpose  the  four  sides  are  made  of  the  purest  Norway 
iron,  as  soft  as  possible  and  thoroughly  annealed.  To  the 
acute  angles  of  the  rhomb  are  connected  the  two  poles  of  a 
long  U-shaped  electro-magnet,  whose  function  is  to  develop 
the  desired  magnetic  potential  difference  at  these  points. 
Connected  to  the  two  obtuse  angles  and  projecting  inward 
are  two  bars  of  Norway  iron,  similar  in  section  to  those 


AND  HIS  INVENTIONS.  213 


2i4  THOMAS  A.  EDISON 

forming  the  sides.  Their  inner  ends,  which  are  hollowed 
out,  approach  to  within  about  a  half  inch  of  each  other. 
Between  these  ends  a  stirrup  is  suspended  by  means  of  a 
silk  fibre,  which  stirrup  carries  a  short  needle,  consisting  of 
a  thin  tube  of  hardened  steel,  well  magnetized.  To  the 
stirrup  is  attached  either  a  pointer  moving  over  a  graduated 
arc,  or  better,  a  mirror,  by  means  of  which  the  defection 
can  be  read  in  the  usual  way  with  a  lampstand  and  scale. 

"In  the  instrument  now  in  use  in  my  laboratory,  the 
magnetic  bridge  is  in  the  form  of  a  rectangle,  as  shown  in 
the  engraving,  the  ends  or  poles  of  the  electro-magnet  being 
connected  to  the  middle  of  the  short  sides,  while  the  bars 
which  pass  inward  to  the  needle  are  joined  to  the  middle  of 
the  longer  sides.  The  four  halves  of  these  longer  sides  con- 
stitute the  sides  of  the  bridge.  The  two  at  one  end  of  the 
rectangle  are  fixed,  the  two  at  the  other  end  are  movable. 
The  two  bars  which  pass  inward  to  the  needle  are  curved  so 
as  to  form  a  semicircle  standing  above  the  plane  of  the 
rectangle.  The  needle  itself  is  similar  in  construction  to 
that  above  described,  but  is  suspended  by  a  wire  attached  to 
a  torsion  head. 

"  It  will  be  readily  seen  that  when  the  electro-magnet  is 
charged,  a  constant  difference  of  magnetic  potential  is 
maintained  at  the  two  ends  of  the  rectangle,  so  that  if  the 
four  bars  constituting  the  sides  of  the  bridge  are  magneti- 
cally identical,  there  will  be  no  difference  of  magnetic 
potential  between  the  ends  of  the  bars  which  pass  to  the 
needle,  and  hence  there  will  be  no  deflection.  But  if  one  of 
the  movable  bars  be  loosened,  the  needle  is  at  once  deflected, 
and  in  a  direction  depending  upon  the  side  the  bar  occupies. 
If  the  bar  is  entirely  removed  the  deflection  is  a  maximum, 
of  course.  And  if  it  be  replaced  by  another  bar  differing  in 
cross-section,  in  quality  of  iron  or  any  other  way  which 
affects  the  magnetic  conductivity  through  the  bridge,  the 


A&&  HIS  INVENTIONS.  215 

deflection  shows  at  once  the  amount  of  difference  between 
th^t  bar  and  the  original  one  taken  as  a  standard.  The 
instrument  is  extraordinarily  delicate,  and  the  principal 
difficulties  encountered  in  using  it  have  arisen  in  the  attempt 
to  preserve  this  delicacy,  while,  at  the  same  time,  the  range 
of  the  apparatus  is  maintained. 

"  The  magnetic  bridge  was  devised  for  the  purpose  of 
testing  readily  the  quality  of  the  iron  purchased  for  the 
construction  of  dynamos.  Very  great  variations  are  observed 
in  irons  supposed,  commercially,  to  be  of  the  same  quality. 
Consequently  the  potential  difference  developed  by  a  dynamo 
having  field  cores  of  such  iron  can  never  be  exactly  calculated. 
But  by  comparing  the  iron  which  is  to  be  thus  used  in  the 
magnetic  bridge,  its  exact  value  for  dynamo  purposes  may 
be  determined,  and  the  constants  of  the  generator  thus 
accurately  calculated  in  advance. 

"  But  this  bridge,  it  would  seem,  will  be  equally  useful  for 
testing  iron  and  steel  for  other  purposes.  By  its  means  not 
only  may  the  character  and  quality  of  the  metal  be  ascertained 
in  terms  of  any  desired  standard,  but  flaws  in  the  interior  of 
a  bar,  such  as  a  car  axle,  may  be  discovered  at  once. 

"  Constructed  with  sufficient  care  and  attention  to  details, 
the  magnetic  bridge  may,  without  doubt,  be  made  a  most 
valuable  instrument  of  precision  for  the  furtherance  of 
scientific  research.  The  theory  of  its  action  is  extremely 
simple,  and  it  is  the  exact  counterpart  of  an  ordinary 
Wheatstone  Bridge,  constructed  for  measuring  low  resistance 
and  immersed  in  salt  water,  since  now  whatever  is  true 
electrically  of  the  one  is  true  magnetically  of  the  other. 
Not  only  may  the  laws  of  magnetic  conductivity  be  in- 
vestigated by  means  of  this  balance  for  all  paramagnetic 
and  diamagnetic  bodies,  but  the  variation  of  this  conductivity 
under  the  action  of  various  physical  agencies,  such  as  heat, 
pressure,  strain,  etc.,  may  be  determined." 


216  THOMAS  A.  EDISON 

Edison's  New  Phonograph. 

AN  INSTRUMENT  THAT  IS  ONE  OF  THE  WONDERS  OF  THE  WORLD 

FULLY  EXPLAINED  IN  EDISON'S  OWN  WORDS. 

ITS    GREAT    FUTURE. 

The  phonograph,  as  first  completed  by  Mr.  Edison  in  1878, 
is  fully  explained  elsewhere  in  this  volume,  with  illustrations 
and  extended  remarks,  as  may  be  seen  on  pages  75  and  9i, 
inclusive.  The  essential  principles  of  this  old  instrument 
have  been  preserved  in  the  new  one,  and  so  many  additional 
valuable  improvements  have  been  made,  that  the  newly 
perfected  phonograph  is  now  one  of  the  genuine  wonders  of 
the  world.  In  a  recent  statement  in  the  North  American 
Review,  Mr.  Edison  has  given  us  a  very  interesting  ac- 
count of  both  the  old  and  new  phonograph,  from  which  we 
make  the  following  extracts  that  fully  explain,  in  Mr.  Edison's 
own  language,  the  new  phonograph. 

"Since  the  time  of  Lucretius,  the  movements  of  atoms 
have  been  invested  with  an  intense  interest  for  philosophers 
and  scientific  students,  and  the  wave-motions  of  light,  heat 
and  sound  have  engaged,  with  a  constantly  increasing  degree 
of  importance,  the  attention  of  modern  investigators.  When 
we  consider  the  relation  of  these  motions  to  mathematics 
and  to  music,  the  conception  of  Pythagoras  that  number 
and  harmony  constituted  the  principle  of  Universe  does  not 
seem  to  be  very  far  out  of  the  way. 

"  In  the  phonograph  we  find  an  illustration  of  the  truth  that 
human  speech  is  governed  by  the  laws  of  number,  harmony  and 
rhythm.  And  by  means  of  these  laws,  we  are  able  to  register  all 
sorts  of  sound  and  all  articulate  utterance — even  to  the  slightest 
shades  and  variations  of  the  voice — in  lines  or  dots  which 
are  an  absolute  equivalent  for  the  emission  of  sound  by  the 
lips;  so  that,  through  this  contrivance,  we  can  cause  these 
lines  and  dots  to  give  forth  again  the  voice,  of  music,  and 


AND  HIS  INVENTIONS. 


2iS  THOMAS  A.  EDISON 

all  other  sounds  recorded  by  them,  whether  audible  or  inaud- 
ible. For  it  is  a  very  extraordinary  fact  that,  while  the 
deepest  tone  that  our  ears  are  capable  of  recognizing  is  one 
containing  16  vibrations  of  sound  a  second,  the  phonograph 
will  record  10  vibrations  or  less,  and  can  then  raise  the  pitch  un- 
til we  hear  a  reproduction  from  them.  Similarly,  vibrations 
above  the  highest  rate  audible  to  the  ear  can  be  recorded  on 
the  phonograph  and  then  reproduced  by  lowering  the  pitch, 
until  we  actually  hear  the  record  of  those  inaudible 
pulsations. 

"  To  make  the  general  idea  of  the  recording  of  sound 
more  clear,  let  me  remark  one  or  two  points.  We  have  all 
been  struck  by  the  precision  with  which  even  the  faintest 
seawaves  impress  upon  the  surface  of  a  beach  the  fine, 
sinuous  line  which  is  formed  by  the  rippling  edge  of  their 
advance.  Almost  as  familiar  is  the  fact  that  grains  of  sand 
sprinkled  on  a  smooth  surface  of  glass  or  wood,  on  or  near 
a  piano,  sift  themselves  into  various  lines  and  curves 
according  to  vibrations  of  the  melody  played  on  the  piano- 
keys.  These  things  indicate  how  easily  the  particles  of 
solid  matter  may  receive  an  imparted  motion,  or  take  an  im- 
pression, from  delicate  liquid  waves,  air  waves,  or  waves  of 
sound.  Yet,  well  known  though  these  phenomena  are,  they 
apparently  never  suggested,  until  within  a  few  years,  that  the 
sound-waves  set  going  by  a  human  voice  might  be  so  directed 
as  to  trace  an  impression  upon  some  solid  substance,  with  a 
nicety  equal  to  that  in  the  tide  in  recording  its  flow  upon  a 
sand  beach. 

"  My  own  discovery  that  this  could  be  done  came  to  me 
almost  accidentally  while  I  was  busy  with  experiments 
having  a  different  object  in  view.  I  was  engaged  upon  a 
machine  intended  to  repeat  Morse  characters,  which  were 
recorded  on  paper  by  indentations  that  transferred  their 
message  to  another  circuit  automatically,  when  passed  under 


AND  HIS  INVENTIONS.  219 

a  tracing-point  connecting  with  a  circuit-closing  apparatus. 
In  manipulating  this  machine  I  found  that  when  the  cylinder 
carrying  the  indented  paper  was  turned  with  great  swiftness, 
it  gave  off  a  humming  noise  from  the  indentations — a 
musical,  rhythmic  sound,  resembling  that  of  human  talk 
heai-d  indistinctly. 

"  This  led  me  to  try  fitting  a  diaphragm  to  the  machine, 
which  would  receive  the  vibrations  or  sound-waves  made 
by  my  voice  when  I  talked  to  it,  and  register  these  vibrations 
upon  an  impressible  material  placed  on  the  cylinder.  The 
material  selected  for  immediate  use  was  paraffined  paper, 
and  the  results  obtained  were  excellent.  The  indentations  on 
the  cylinder,  when  rapidly  revolved,  caused  a  repetition  of 
the  original  vibrations  to  reach  the  ear  through  a  recorder, 
just  as  if  the  machine  itself  were  speaking.  I  saw  at  once 
that  the  problem  of  registering  human  speech,  so  that  it  could 
be  repeated  by  mechanical  means  as  often  as  might  be 
desired,  was  solved. 

"It  may  be  of  interest,  here,  to  contrast  briefly  the  perfected 
phonograph  with  the  mere  exhibition  models  shown  all  over 
the  world,  in  1878.  Those  models  were  large,  heavy 
machines  which  purposely  sacrificed  distinctness  of  articu- 
lation, in  order  to  secure  a  loud  tone  which  could  be  heard  in 
a  large  room  when  emitted  through  a  funnel-shaped  transmit- 
ter. Tin-foil  was  used  as  the  material  on  which  the  indent- 
ations were  to  be  made.  The  cylinders  were  revolved  by 
hand,  or  by  clock-work;  and  there  were  numerous  other 
details  of  construction  which  differed  from  those  of  the 
instrument  as  now  completed.  At  that  time  I  had  made 
various  designs  for  a  special  kind  of  electric  motor,  differing 
from  all  others,  to  run  the  machine,  in  place  of  clock-work; 
and  the  phonograph,  as  we  now  manufacture  it,  is  provided 
with  such  a  motor,  which  turns  the  cylinder  noiselessly, 
uniformly  and  easily. 


220  THOMAS  A.  EDISON 

"Instead  of  tin-foil,  I  now  use  a  cylinder  of  wax  fo 
receiving  the  record  of  sound-pulsations,  as  in  the  original 
experiments.  One  diaphragm  (the  'recorder')  receives 
these  pulsations,  which  are  incised  on  the  wax,  in  exceedingly 
fine  lines,  hardly  visible  to  the  naked  eye,  by  means  of  a 
small  point  pressing  against  the  wax.  A  turning-tool  attach- 
ment, near  this  recording  diaphragm,  pares  off  the  surface 
of  the  wax,  removing  any  record  which  may  previously 
have  been  left  there,  and  smoothing  the  way  for  whatever 
you  wish  to  speak  into  the  '  recorder.'  When  you  have 
finished  speaking,  two  simple  motions  bring  the  reproducing 
diaphragm  into  place  directly  over  the  wax;  and  this 
diaphragm,  provided  with  a  very  delicate  but  durable 
needle,  takes  up  and  reproduces  the  vibrations  registered  in 
the  fine  lines  of  indentations,  bringing  them  to  the  ear  by 
means  of  a  tube. 

"Sometimes,  indeed,  one  can  hear  the  recorded  words  as 
they  are  thrown  off  by  the  needle  from  the  revolving  cylinder, 
without  using  a  tube  at  all,  and  by  simply  putting  the  ear 
close  to  the  wax.  The  adjustments  of  these  receiving  and 
transmitting  diaphragms,  known  as  the  '  recorder  '  and  the 
'reproducer,'  are  very  exact,  but  very  easily  arranged.  And 
a  machine,  once  adjusted  after  being  set  up,  will  run  well 
with  very  little  attention  or  re-adjustment  for  a  long  period 
of  time.  The  battery,  also,  conveniently  placed  in  a  box 
under  the  desk  which  holds  the  instrument,  will  last  for  six 
weeks  or  more,  according  to  use,  without  renewal.  A  scale 
and  indicator  running  the  whole  length  of  the  cylinder,  in 
front,  enable  you  to  observe  at  what  point  you  began  talking 
so  that  the  reproducer  may  be  set  at  that  point  on  the  wax 
as  soon  as  you  wish  to  take  off  the  record." 

Another  very  handy  attachment  supplies  a  key  for  sus- 
pending the  reproduction  of  sounds  when  it  is  going  on  too 
rapidly  for  the  copyist,  who  is  writing  it  out.  A  second 


AND  HIS  INVENTIONS.  221 

key  when  pressed  down  will  run  the  reproducer  back 
so  as  to  repeat  anything  which  has  not  been  clearly  under- 
stood, and  this  may  be  done  any  desired  number  of  times. 
A  single  wax  cylinder,  or  blank,  may  be  used  for  fifteen  or 
twenty  successive  records  before  it  is  worn  out.  But  if  the 
record  is  to  be  kept,  the  wax  blank  must  not  be  talked  upon 
again,  and  is  simply  slipped  off  from  the  metal  cylinder  and 
filed  away  for  future  reference.  It  may  be  fitted  on  to  the 
cylinder  again  at  any  time,  and  will  at  once  utter  whatever 
has  been  registered  on  it.  One  of  these  wax  blanks  will 
repeat  its  contents  thousands  of  times  with  undiminished 
clearness.  Further,  we  are  able  to  multiply  to  any  extent,  at 
slight  cost,  phonographic  copies  of  the  blank,  after  the  talking, 
or  music,  or  other  sounds,  have  been  put  upon  it  once. 

It  is  curious  to  reflect  that  the  Assyrians  and  the 
Babylonians,  2,500  years  ago,  chose  baked  clay  cylinders, 
inscribed  with  cunei-form  characters,  as  their  medium  for 
perpetuating  records;  while  this  recent  result  of  modern 
science,  the  phonograph,  uses  cylinders  of  wax  for  a  similar 
purpose,  but  with  the  great  and  progressive  difference  that 
our  wax  cylinders  speak  for  themselves,  and  will  not  have  to 
wait  dumbly  for  centuries  to  be  deciphered,  like  the  famous 
Kileh-Shergat  cylinder,  by  a  Rawlinson  or  a  Layard.  With 
our  facilities,  a  sovereign,  a  statesman,  or  a  historian,  can 
inscribe  his  words  on  a  phonograph  blank,  which  will  then 
be  multiplied  a  thousand-fold;  each  multiple  copy  will  repeat 
the  sounds  of  his  voice  thousands  of  times;  and  so,  by  reserv- 
ing the  copies  and  using  them  in  relays,  his  utterance  can  be 
transmitted  to  posterity,  centuries  afterwards,  as  freshly  and 
forcible  as  if  those  later  generations  heard  his  living  accents. 

Instrumental  and  vocal  music — solos,  duets,  quartets, 
quintets,  etc.,  can  be  recorded  on  the  perfected  phonograph 
with  startling  completeness  and  precision.  How  interesting 
it  will  be  to  future  generations  to  learn  from  the  phonograph 


222  THOMAS  A.  EDISON' 

exactly  how  Rubinstein  played  a  composition  on  the  piano; 
and  what  a  priceless  possession  it  would  have  been  to  us 
could  we  have  Gen.  Grant's  memorable  words,  "Let  us  have 
peace,"  inscribed  on  the  phonograph  for  perpetual  reproduct- 
on  in  his  own  intonations !  We  are  in  a  position  to  obtain 
results  of  this  sort  by  the  present  phonograph,  from  the 
wave-motions  of  sound;  so  that  it  seems  to  me  we  realize 
here  the  "poetry  of  motion"  in  a  new  sense,  combined  with 
the  science  of  motion. 

In  my  article  ten  years  ago,  I  enumerated  among  the  uses 
to  which  the  phonograph  would  be  applied  :  1.  Letter  writ- 
ing and  all  kinds  of  dictation  without  the  aid  of  a  sten- 
ographer. 2.  Phonographic  books,  which  would  speak  to 
blind  people  without  effort  on  their  part.  3.  The  teaching 
of  elocution.  4.  Reproduction  of  music.  5.  The  "Family 
Record"  — a  registry  of  sayings,  reminiscences,  etc.,  by 
members  of  a  family,  in  their  own  voices,  and  of  the  last 
words  of  dying  persons.  6.  Music  boxes  and  toys. 
7.  Clocks  that  should  announce  in  articulate  speech  the  time 
for  going  home,  going  to  meals,  etc.  8.  The  perservation 
of  languages,  by  exact  reproduction  of  the  manner  of 
pronouncing.  9.  Educational  purposes;  such  as  preserving 
the  explanations  made  by  a  teacher,  so  that  the  pupil  can 
refer  to  them  at  any  moment,  and  spelling  or  other  lessons 
placed  upon  the  phonograph  for  convenience  in  committing 
to  memory.  10.  Connection  with  the  telephone,  so  as  to 
make  that  invention  an  auxiliary  in  the  transmission  of  per 
manent  and  invaluable  records,  instead  of  being  the 
recipient  of  momentary  and  fleeting  communications. 

Every  one  of  these  uses  the  perfected  phonograph  is  now 
ready  to  carry  out.  I  may  add  that,  through  the  facility 
with  which  it  stores  up  and  reproduces  music  of  all  sort,  or 
whistling  and  recitations,  it  can  be  employed  to  furnish  con- 
stant amusement  to  invalids,  or  to  social  assemblies,  at 


AND  HIS  INVENTIONS.  223 

receptions,  dinners,  etc.  Any  one  sitting  in  his  room  alone 
may  order  an  assorted  supply  of  wax  cylinders  inscribed  with 
songs,  poems,  piano  or  violin  music,  short  stories  or  anec- 
dotes or  dialect  pieces,  and,  by  putting  them  on  his 
phonograph,  he  can  listen  to  them  as  originally  sung  or 
recited  by  authors,  vocalists  and  actors,  or  elocutionists.  The 
variety  of  entertainment  he  thus  commands,  at  trifling 
expense  and  without  moving  from  his  chair,  is  practically 
unlimited.  Music  by  a  band,  in  fact,  whole  operas,  can  be 
stored  up  on  the  cylinders,  and  the  voice  of  Patti  singing  in 
England  can  thus  be  heard  again  on  this  side  of  the  ocean,  or 
preserved  for  future  generations. 

On  four  cylinders  eight  inches  long,  with  a  diameter  of 
five,  I  can  put  the  whole  of  "Nicholas  Nickleby"  in 
phonogram  form.  In  teaching  the  correct  pronunciation 
of  English,  and  especially  of  foreign  languages,  the 
phonograph  as  it  stands  seems  to  be  beyond  comparison,  for 
no  system  of  phonetic  spelling  can  convey  to  the  pupil  the 
pronunciation  of  a  good  English,  French,  German  or 
Spanish  speaker  so  well  as  a  machine  that  reproduces  his 
utterances  even  more  exactly  than  a  human  imitator  could. 

The  speeches  of  orators,  the  discourses  of  clergymen,  can 
be  had  "  on  tap  "  in  every  house  that  owns  a  phonograph. 
It  would  not  be  very  surprising  if,  a  few  years  hence, 
phonographic  newspaper  bulletins  should  be  issued  on  wax 
cylinders.  Even  now,  so  soon  as  the  phonograph  comes 
into  general  use,  newspaper  reporters  and  correspondents 
can  talk  their  matter  into  the  phonograph,  either  in  the 
editorial  office  or  at  some  distant  point,  by  a  telephone  wire 
connected"  with  a  phonograph  in  the  composing-room,  so 
that  the  communication  may  be  set  up  in  type  without  any 
preliminary  of  writing  it  out  in  long  hand. 

The  wax  cylinders  can  be  sent  through  the  mails  in  little 
boxes  which  I  have  prepared  for  that  purpose,  and  then  put. 


224  THOMAS  A.  EDISON' 

upon  another  phonograph  at  a  distant  point,  to  be  listened  to 
by  a  friend  or  business  correspondent.  To  obviate  the 
difficulty  caused  by  the  friend's  not  having  a  phonograph  of 
his  own,  pay  stations  will  be  established,  to  which  any  one 
may  take  the  phonogram  that  he  has  received,  have  it  placed 
on  the  instrument,  and  the  contents  recited  to  him  from  the 
machine,  as  well  as  copied  out  at  the  same  moment  by  a 
type-writer.  Thus  the  phonograph  will  be  at  the  service 
of  every  one  who  can  command  a  few  cents  for  the  fee.  And 
which  of  us  would  not  rather  pay  something  extra  in  order 
to  hear  a  dear  friend's  or  relative's  voice  speaking  to  us 
from  the  other  side  of  the  earth? 

Authors  can  register  their  fleeting  ideas  and  brief  notes 
on  the  phonograph  at  any  hour  of  day  or  night,  without 
waiting  to  find  pen,  ink,  or  paper,  and  in  much  less  time  than 
it  would  take  to  write  out  even  the  shortest  memoranda. 
They  can  also  publish  their  novels  or  essays  exclusively  in 
phonogram  form,  so  as  to  talk  to  their  readers  personally; 
and  in  this  way  they  can  protect  their  works  from  being 
stolen  by  means  of  defective  copyright  laws.  Musical  com- 
posers, in  improvising  compositions,  will  be  able  to  have 
them  recorded  instantaneously  on  the  phonograph. 

For  the  present  it  has  been  decided  to  make  all  the 
phonographs  of  uniform  size;  so  that  a  record  put  upon  the 
machine  in  New  York  may  be  placed  on  another  machine 
of  the  same  pattern  in  China,  and  speak  exactly  as  it  was 
spoken  to  on  this  continent.  Each  wax  blank  will  receive 
from  800  to  1,000  words;  and,  of  course,  several  blanks 
may  be  used  for  one  document,  if  needed.  This  uniform 
size  and  pattern  make  the  thing  perfectly  practicable  in 
offices  which  have  business  connections  all  over  the  globe. 
My  private  secretary  to-day  speaks  all  letters  into  a 
phonograph,  from  which  they  are  taken  off  by  a  type-writer 
or  ordinary  long-hand-writer,  with  an  immense  saving  of 


AND  HIS  INVENTIONS.  225 

time  and  trouble.  Persons  having  a  large  correspondence 
can  talk  all  their  letters  into  the  phonograph  in  a  very  short 
time,  and  leave  them  to  be  listened  to  and  copied  by  an 
assistant,  without  the  delay  involved  in  stenography  or  the 
trouble  of  going  over  and  correcting  the  copyist's  work,  which 
is  almost  inevitable  under  the  conditions  of  dictation  now 
prevailing. 

Furthermore,  two  business  men,  conferring  together,  can 
talk  into  the  recorder  by  means  of  a  double  transmitting 
tube,  with  perfect  privacy,  and  yet  obtain  upon  the  cylinder 
an  unimpeachable  transcript  of  their  conversation  in  their 
own  voices,  with  every  break  and  pause,  every  hesitation  or 
confident  affirmation,  every  partial  suggestion  or  particular 
explanation,  infallibly  set  down  in  the  wax.  They  can 
then  have  this  conversation  written  out  or  typed  by  a  secretary 
for  future  reference;  or  can,  if  they  prefer,  have  it  multiple- 
copied  by  our  mechanical  process.  In  this  way  many  mis- 
understandings may  be  avoided.  Interesting  philosophic  or 
literary  discussions  and  dialogues  may  be  recorded  in  the 
same  way.  In  fact,  the  phonograph  will  do,  and  does  at  this 
moment  accomplish,  the  same  thing  in  respect  of  conversation 
which  instantaneous  photography  does  for  moving  objects; 
that  is,  it  will  present  whatever  it  records  with  a  minute 
accuracy  unattained  by  any  other  means. 

The  most  skillful  observers,  listeners  and  realistic  novelists, 
or  even  stenographers,  cannot  reproduce  a  conversation 
exactly  as  it  occurred.  The  account  they  give  is  more  or 
less  generalized.  But  the  phonograph  receives,  and  then 
transmits  to  our  ears  again,  every  least  thing  that  was  said — 
exactly  as  it  was  said — with  the  faultless  fidelity  of  an 
instantaneous  photograph.  We  shall  now  for  the  first  time 
know  what  conversation  really  is;  just  as  we  have  learned, 
only  within  a  few  years,  through  the  instantaneous 
photograph,  what  attitudes  are  taken  by  the  horse  in  motion. 


226  THOMAS  A.  EDISON 

Letters  of  introduction  may  be  spoken  onto  a  phonograph 
blank,  without  any  of  the  formality  of  address  and  phraseology 
now  customary,  or  the  trouble  of  folding,  enveloping  and 
addressing  a  written  communication.  In  fact,  all  correspond- 
ence will  be  greatly  simplified  and  wisely  abbreviated  by 
the  use  of  phonograms.  A  telephone  subscriber  can  place 
at  his  telephone  a  phonogram  which  will  announce  to  the 
exchange,  whenever  he  is  called  up,  that  he  has  left  the 
office  and  will  return  at  a  certain  time. 

Similarly,  one  man  calling  at  the  office  of  another  and  not 
finding  him,  will  talk  into  the  phonograph  anything  he 
wishes  to  say.  This  saves  the  trouble  of  writing  a  note,  and 
obviates  the  uncertainty  of  giving  to  'clerk,  office-boy  or 
servant,  an  oral  message  that  may  be  forgotten  or  incorrectly 
delivered.  Hotels  and  clubs  will,  naturally,  find  this 
function  of  the  phonograph  extremely  servicable;  and  their 
guests  and  patrons  will  avail  themselves  of  phonograms 
constantly.  The  accuracy  of  interviews  with  newspaper 
reporters  will  also  be  determined,  no  doubt,  by  phonographic 
record.  And  travelers  in  vestibule  trains  will  be  glad  to  use 
phonograph  blanks  in  place  of  letter  paper  and  telegraph 
blanks,  owing  to  the  difficulty  of  writing  while  on  a  rapidly 
moving  train. 

It  must  be  borne  in  mind  that  I  am  not  talking  now  of 
things  which  may  be  made  possible  in  the  future.  I  did 
my  predicting  ten  years  ago;  and  the  functions  above 
mentioned  are  those  which  the  present  perfected  phonograph 
is  able  to  fulfill  at  this  moment.  To  use  the  phonograph, 
a  little  instruction  and  practice  are  needed,  but  much  less 
than  the  type-writer  requires  and  hardly  more  than  the 
training  needed  for  the  operation  of  a  sewing-machine. 

Various  other  uses  for  which  the  phonograph  is  now  fully 
ripe  might  be  mentioned;  but  I  do  not  want  to  give  to  these 
memoranda  the  character  of  a  catalogue.  Enough  has  been 


AND  HIS  INVENTIONS. 


227 


228  1HOMAS  A.  EDISON 

said,  I  think,  to  indicate  that  the  phonograph,  unlike  children, 
should  be  "seen "  and  "  heard."  It  is  no  longer  in  a  state 
of  infancy.  It  may  be  still  in  its  childhood;  but  it  is  destined 
to  a  vigorous  maturity.  The  phonograph,  in  one  sense, 
knows  more  than  we  do  ourselves,  for  it  will  retain  a  per- 
fect mechanical  memory  of  many  things  which  we  may 
forget,  even  though  we  have  said  them.  It  will  become  an 
important  factor  in  education;  and  it  will  teach  us  to  be 
careful  what  we  say— for  it  imparts  to  us  the  gift  of  hearing 
ourselves  as  others  hear  us — exerting  thus  a  decidedly  moral 
influence  by  making  men  brief,  businesslike  and  straight- 
forward, cultivating  improved  manners,  and  uniting  distant 
friends  and  associates  by  direct  vocal  communication. 


The  Phonograph  and  Music. 

Mr.  Edison's  newly  perfected  phonograph,  by  its  musical 
achievements,  cannot  fail  to  interest  all  music  lovers,  and 
especially  those  musicians  who  long  to  know  the  exact 
peculiarities  of  time  and  rhythm  adopted  by  the  great  com- 
posers in  conducting  their  own  works.  Had  Beethoven 
possessed  a  phonograph,  the  musical  world  would  not  be  left 
to  the  uncertainties  of  metronomic  indications  which  we 
may  interpret  wrongly,  and  which  at  best  are  but  feeble 
suggestions;  while  Mozart,  who  had  not  even  a  metronome, 
might  have  saved  his  admirers  many  a  squabble  by  giving 
the  exact  fashion  in  which  he  wished  his  symphonies  to  be 
played.  According  to  all  accounts,  the  phonograph  will 
give  the  true  time  of  a  piece  of  music,  no  matter  how  con- 
stant or  how  delicate  the  variations. 

There  seems  to  be  no  reason  to  doubt  that  it  will  give  a 
fair  echo  of  a  musical  performance.  All  musicians  will  see 
at  once  of  what  immense  value  even  an  accurate  echo,  in 
time  and  tune,  may  be.  It  will  give  the  student  the  phrasing 
of  great  soloists — something  which  no  expression  marks  can 


AND  HIS  INVENTIONS.  11$ 

Convey.  Future  generations  will  be  able  to  learn,  if  they 
care  to  know,  exactly  how  Rubinstein  "phrased"  the 
"  Emperor  "  concerto,  or  with  what  mannerisms  Mme.  Patti 
sang  "  Home,  Sweet  Home  ";  they  will  be  able  to  compare 
the  manner  in  which  one  famous  conductor  led  the  master- 
pieces of  musical  art  with  the  conception  of  his  rivals;  and 
will  know  infinitely  more  about  the  music  of  to-day  than  we 
know  of  the  music  of  our  ancestors.  Finally,  the  old  gentle- 
man, slightly  deaf,  who  insists  that  there  is  no  such  music 
nowadays  as  was  to  be  heard  in  his  youth,  will  be  brought  to 
book  almost  literally,  and  be  confounded  with  phonographic 
proofs  to  the  contrary. 


The  Funny  Side  of  the  Phonograph  as 
Seen  by  Col.  Knox. 

"The  phonograph,"  says  the  Colonel,  "will  soon  be  <in 
our  midst.'  The  inventor  says  that  it  is  perfected  and  is 
being  manufactured  for  sale.  When  we  get  one  we  shall 
merely  have  to  talk  to  it,  and  it  will  record  every  articulate 
sound;  then  at  any  time  in  the  future  we  shall  have  only  to 
turn  the  handle  of  the  thing  and  it  will  reproduce  the  words, 
the  tone  and  the  accent  exactly  as  received  from  us. 

"  Possibly  the  instrument  may  be  developed  until  vest- 
pocket  phonographs  are  made,  and  we  can  all  carry  them 
around  with  us  and  collect  the  flashes  of  folly  and  whisper- 
ings of  wisdom  expressed  to  us  by  our  friends  and  acquaint- 
ances. There  will  be  advantages  and  disadvantages  in  this. 
The  autograph  pest  will  throw  away  his  album  and  buy  a 
phonograph.  He  will  come  around  and  present  the  muzzle 
of  the  instrument  to  you  and  request  you  to  load  it  up  with 
a  few  remarks  to  be  preserved,  so  that  they  may  be  fired  off 
at  future  generations.  The  opera  singer  will  be  asked  to 
warble  a  carol  into  its  lungs,  and  the  statesman  to  fill  its 
throttle  with  his  views  on  the  political  problems  of  the  hour, 
and  these  will  be  duplicated,  as  a  woodcut  or  steel  engraving 


230  THOMAS  A.  EDISON 

is,  and  amateur  phonographers  will  make  private  collections 
of  all  sorts  of  sounds,  from  the  hoarse  toot  of  a  foghorn  to 
the  soft  sibilant  swish  of  an  unripe  picnic  kiss,  and  will 
reproduce  them  at  will. 

"And  Mrs.  Jones  will  set  the  trigger  of  her  phono  when 
Jones  comes  home  at  2  A.  M.,  and,  pursuing  him  around  the 
room,  will  capture  every  lie  he  tells  and  every  hiccough  he 
hies,  and  even  the  noise  he  makes  falling  over  his  feet,  and 
at  the  breakfast  table  next  morning  she  will  turn  it  loose  on 
him  and  paralyze  him  with  his  own  abbreviated  words  and 
tangled  language  of  the  night  before,  and  he  will  be  much 
embarrassed  thereat. 

"Again  there  is  the  reporter;  he  will  use  it,  and  when  you 
tell  him  that  you  are  'not  a  candidate,  and  would  not,  under 
any  circumstances,  accept  the  nomination  if  tended,'  he  will 
file  away  your  remarks  until  you  deny  that  you  ever  uttered 
them,  and  then,  from  his  inside  pocket,  he  will  draw  forth 
his  phonograph  and  you  will  wish  you  had  bought  a  time 
lock  for  your  mouth. 

"Pity,  isn't  it,  that  the  phonograph  was  not  invented  a  few 
thousand  years  ago,  because  if  it  had,  down  through  the  cor- 
ridors of  time  might  have  reverberated  the  echoes  of  the 
great  events  of  the  past,  and  we  of  to-day  could  have  taken 
our  phonos  out  on  the  back  stoop  in  the  long  summer 
evening  and  listen  to  the  roar  of  the  lions  in  Daniel's  den, 
the  sound  of  Nero's  fiddle  and  the  clatter  of  the  Roman 
Empire  as  she  fell. 

"If  this  wonderful  instrument  is  possible  why  may  it  not  be 
possible  to  invent  a  machine  that  will  take  our  unvoiced 
thoughts  as  we  think  them,  and  record  them  in  some  way  so 
that  they  may  be  afterward  transferred  to  paper?  What 
vagaries  of  thought  the  thinkograph  would  reveal — what 
delirium  tremens  of  imaginings  would  it  disclose  !  In  cold 
type  they  would  astonish  even  the  thinker." 


AND  HIS  INVENTION'S.  231 

The  Doll  Baby  Phonograph 

Edison's  phonograph  has  resulted  in  a  patent  for  a  com- 
bined doll  and  phonograph,  issued  May  22,  1888,  that 
promises  to  be  a  very  interesting  and  profitable  application 
of  the  principles  of  that  wonderful  device.  It  is  a  child's 
doll,  in  which  a  small  phonograph  is  fixed,  that  makes  it 
quite  practicable  as  a  toy.  And  as  it  can  be  put  to  so  many 
useful  purposes  as  a  kindergarten  apparatus,  etc.,  it  would 
seem  to  be  something  more  than  a  toy.  It  at  once  suggests 
a  great  variety  of  very  useful  applications  of  the  phonograph 
for  the  pleasure,  as  well  as  the  instruction,  of  the  little  folks, 
who  would,  through  its  medium,  be  placed  in  command  of 
an  automatic  story-teller,  and  have  Jack,  the  Giant-Killer, 
and  all  the  other  phantasmagoria  of  childhood,  brought  to 
their  attention  in  the  most  vivid  and  interesting  manner. 


A  Story  of  Edison— Hurrying-  up  the 
Phonograph. 

As  illustrating  the  versatility  and  fecundity  of  Mr.  Edison, 
the  inventor,  Mr.  Edward  H.  Johnson,  of  the  Edison  Light 
Company,  tells  the  following  little  story :  "  I  was  traveling," 
says  he,  "  through  the  west  for  Edison,  giving  exhibitions  of, 
and  lectures  on,  the  telephone.  Edison  had  previously  told 
me  in  a  casual  way  that  he  believed  he  could  make  a  talking 
machine,  and  he  meant  to  do  it  some  day.  In  a  burst  of 
enthusiasm  at  Buffalo,  I  boasted  that  the  wizard  would 
astonish  them  still  more  as  soon  as  he  could  find  time  to 
perfect  his  talking  machine.  The  audience  went  wild  over 
the  announcement,  and  it  was  some  minutes  before  I  could 
proceed  with  my  lecture.  At  its  conclusion  I  was  besieged 
and  congratulated  by  an  eager  crowd,  who  extorted  from  me 
a  promise  that  I  would  hurry  up  that  talking  machine  and 
exhibit  it  first  in  Buffalo. 

"  I  abandoned  the  remainder  of  my  trip,  packed  my  grip- 


232  THOMAS  A.  EDISON" 

sack  and  started  for  Newark  that  night.  All  the  way 
home  I  was  wondering  whether  I  hadn't  bit  off  more  than  I 
could  chew." 

"Tom,"  says  I,  as  soon  as  I  could  reach  him,  "  you  must  let 
everything  else  go,  and  finish  that  talking  machine  without 
delay.  The  people  are  crazy  over  it.  I  made  a  bluff  at  them 
in  Buffalo,  and  the  whole  audience  called  me  down." 

"All  right,"  said  Edison, unconcernedly. 

"  In  three  days  he  received  from  New  York  the  metal 
cylinder,  and  before  nightfall  the  phonograph  was  an 
accomplished  fact." 


Edison  Experimenting  with  the  Baby  and 
the  Phonograph. 

It  is  facetiously  remarked  of  Mr.  Edison  that  he  has  ex- 
perimented extensively  with  a  phonograph  and  his  new 
baby  at  home.  He  found  that  when  the  baby  crowed  with 
glee,  the  crow  was  registered  perfectly  on  the  phonograph; 
when  it  got  mad  and  yelled,  its  piercing  screams  were 
irrevocably  recorded  on  the  same  machine.  That  phonograph 
is  now  a  receptacle  of  every  known  noise  peculiar  to  baby- 
hood. It  is  Mr.  Edison's  intention  to  take  a  record  of  the 
strength  of  baby's  lungs  every  three  months.  "I  will  preserve 
the  record,"  says  he,  "  until  the  child  becomes  a  young  lady. 
Then  the  phonograph  can  be  operated  for  her  benefit,  and 
she  can  see  for  herself  just  what  kind  of  a  baby  she  was, 
and  won't  have  to  take  her  mother's  and  the  nurse's  words 
for  it." 


AND  HIS  INVENTIONS.  233 

Edison's  Opinion  of  the  Patent  Law. 

A  PLAIN,  PUNGENT  STATEMENT  FOB  CONGRESSMEN. 

"I  always  thought,"  said  Mr.  Edison,  recently,  on  the 
subject  of  the  Patent  Law,  "that  my  original  patent  of 
twelve  years  ago  covered  the  essential  features  of  the 
phonograph  so  completely  as  to  give  me  a  monopoly  of  the 
perfected  instrument  whenever  I,  or  any  one  else,  should 
find  time  to  finish  it.  Within  the  last  few  years,  however,  I 
have  become  extremely  skeptical  as  to  the  value  of  any 
patent,  and  so  long  as  our  patent  law  remains  in  its  present 
iniquitous  shape,  I  shall  try  to  do  without  patents. 

"The  present  law  is  a  constant  temptation  to  rascals,  and 
virtually  offers  a  premium  on  rascality.  Under  it  the  in- 
fringer  of  a  patent  is  not  interfered  with  until  the  real 
owner  can  show  that  he  has  the  monopoly  of  the  device  in 
question.  This  process  may  take  years,  during  which  the  in- 
fringer,  who  has  money  and  audacity  enough  to  secure 
another  man's  invention,  can  go  on  and  perhaps  wear  the 
rightful  owner's  life  out  by  litigation  and  annoyance.  I 
have  had  so  much  of  this  sort  of  thing  within  the  last  five 
years,  that  I  have  almost  made  up  my  mind  never  to  take 
out  another  patent  until  the  law  is  changed.  The  burden  of 
proof  is  now  put  entirely  on  the  man  who  holds  the  patent 
instead  of  the  man  who  wishes  to  infringe  it,  whereas  it 
ought  to  be  all  the  other  way. 

"There  is  scarcely  an  invention  of  importance  made 
within  the  last  generation,  which  has  not  been  disputed  upon 
frivolous  grounds,  and  the  inventor  put  to  all  sorts  of 
annoyance.  In  my  own  case,  I  am  sure  that  no  matter  what 
I  may  patent,  some  one  will  come  up  as  soon  as  the  patent  is 
seen  to  have  any  value,  and  shows  by  dozens  of  witnesses,  if 
necessary,  that  he  is  the  rightful  owner  of  the  invention. 

"If  I  patent  to-morrow  a  process  for  making  good  flour  at 


234  THOMAS  A.  EDISON 

a  cost  of  two  cents  a  barrel,  the  publication  of  my  patent 
would  bring  out  about  ten  men  who  could  prove  that  they 
did  that  sort  of  thing  years  ago,  and  that  I  had  no  right  to  a 
patent. 

"  In  the  case  of  my  dynamos,  I  have  patents  by  the  score, 
and  yet  when  a  great  firm  of  machinists  want  to  go  into  the 
business  of  making  dynamos,  they  coolly  appropriate  one 
hundred  of  my  inventions,  and  laugh  at  my  claims  as 
patentee.  To  litigate  the  matter  to  the  end,  if  there  was 
any  end  in  sight,  would  cost  hundreds  of  thousands  of 
dollars,  and  put  me  in  hot  water  for  years  to  come.  I  am 
an  inventor  and  not  a  lawyer,  and  I  hate  litigation.  If 
patents  are  going  to  give  me  nothing  but  law-suits,  I  don't 
want  any  more  of  them. 

"  In  case  of  the  phonograph  these  Washington  people  have 
had  the  decency  to  come  here  to  Orange  and  ask  for  my  permis- 
sion to  manufacture  and  sell  their  devices;  they  wanted  a 
license,  which  I  refused  to  give  them.  Having  no  license, 
they  go  to  work  at  once  and  proclaim  the  worthlessness  of 
all  patents  upon  the  phonograph  except  their  own;  they  have 
got  some  patents  for  twisting  a  screw  to  the  right  instead  of 
the  left,  etc.  I  really  can't  say  what  our  first  steps  will  be,  and 
I  leave  all  those  matters  to  the  lawyers,  who  enjoy  that  sort 
of  business.  Certainly  if  the  phonograph  turns  out  to  be 
the  great  success  that  I  expect  for  it,  there  will  be  a  dozen 
infringements  upon  the  market  within  the  next  six  months, 
and  the  lawyers  will  have  their  hands  full. 

"I  am  so  thoroughly  convinced  of  the  uselesseness  of  pat- 
ents, thatoneof  the  objects  in  building  my  present  laboratory 
is  to  search  for  trade  secrets  that  require  no  patents,  and  may 
be  sources  of  profit  until  some  one  else  discovers  them.  There 
are  scores  and  scores  of  such  secret  processes,  which  are 
enormously  profitable  and  which  are  not  claimed  right  and 
left,  just  because  they  are  secrets.  Some  of  them  are  used 


AND  HIS  INVENTIONS.  235 

in  this  country,  but  most  of  them,  chiefly  chemical,  are  held 
in  Europe.  Methods  of  dyeing,  of  working  certain  fabrics, 
etc.,  pay  millions  every  year  to  those  who  know  the  secret 
processes  employed." 

"I  have  already  found  one  chemical  device  which  promises 
to  pay  me  handsomely,  and  the  patent  office  will  never  hear 
anything  about  it.  To  apply  for  a  patent  would  simply 
invite  a  lot  of  rogues  to  share  with  me,  or,  what  is  more 
likely,  to  take  all  the  profits.  1  am  rather  curious  to  see  what 
is  to  be  done  when  the  phonograph  comes  out.  The  patent 
has  only  five  years  to  run,  and,  evidently,  if  men  with 
millions  behind  them  jump  into  the  manufacture  upon  a 
large  scale,  the  patent  may  run  out  before  my  claim  to  the 
fundamental  device  is  allowed. 

The  reader  must  not  infer  that  Mr.  Edison  has  been 
deprived  of  all  his  just  rights  and  dues  in  the  patent  business 
generally.  By  no  means.  He  occupies  one  of  the  very  finest 
estates  in  the  vicinity  of  New  York  City,  and,  as  has  been 
remarked,  "  if  he  is  not  twice  a  millionaire,  it  can  be  for  no 
other  reason  than  that,  like  too  many  of  us,  he  has  found  it 
less  easy  to  keep  money  than  it  is  to  get  it."  In  addition  to 
this  he  has  now  sold  out  his  phonograph  to  a  large  and  com- 
petent company  for  a  "cool  million"  which  must  very 
materially  augment"  his  bank  account. 


236  THOMAS  A.  EDISOX 


OFFICES  AND  SHOW  ROOMS  OF  THE  EDISON  UNITED  MANTJFAOTTJBINQ 
COMPANY,  NEW  YOBK. 


ELECTRICAL  DICTIONARY  AND  EXPLANATIONS. 


The  very  rapid  development  of  electricity  in  its  wide 
scope  of  general  and  useful  application  in  art,  science  and 
human  progress  in  this  country  and  throughout  the  civilized 
world,  which  necessarily  requires  the  coining  of  many  new 
words  and  phrases  that  even  a  "  Webster  "  cannot  keep  pace 
therewith,  has  rendered  this  Electrical  Dictionary  and 
explanation  of  terms  a  necessity,  which  will  not  only  greatly 
aid  the  reader  in  pursuing  electrical  literature  generally, 
but,  perhaps,  supplement  his  knowledge  of  this  wonderful 
science  and  help  him  to  keep  abreast  of  this  "Electric 
Age." 

Absolute  Unit— "That  force  which,  acting  upon  a  mass 
of  one  gramme  for  one  second,  is  able  to  give  it  a  velocity 
of  one  centimeter  per  second."  It  is  called  the  "  absolute 
unit,"  because,  in  fact,  one  gramme  is  the  unit  of  mass,  one 
centimeter,  the  unit  of  length,  and  one  second,  the  unit  of 
time.  It  is  also  known  as  the  "  C.  G.  S.  unit,"  adopted  at 
the  Paris  Congress  of  Scientists  in  1882,  and  made  on  that 
occasion  the  basis  of  electrical  measurements.  The  exact 
amount  of  force  requisite  to  move  one  gramme  one  centi- 
meter in  one  second,  is  a  most  important  point  to  fix  in  the 
mind,  for  it  is  the  basis  of  the  mathematics  of  electricity, 
and  the  "  absolute  unit"  to  which  all  other  units  are  referred 
or  adjusted.  Its  symbols  are  C.  G.  S.,  the  C.  representing 
Centimeter  (space),  G.  Gramme  (mass),  and  S.  Second  (time). 
A  centimeter  is  about  2-5  of  an  inch,  and  a  gramme  is  nearly 
15^  grains. 


238  ELECTRICAL  DICTIONARY 

Accelaration— The  rate  of  change  of  velocity. 

Accumulator— An  apparatus  for  receiving  and  retaining 
large  quantities  of  electricity. 

Amalgam— A  compound  of  mercury  with  another  metal; 
used  in  coating  electric  plates. 

Ampere— The  practical  unit  of  current  strength,  or  "flow 
of  current,"  named  after  Ampere.  It  is  equal  to  the  current 
produced  in  a  circuit  of  one  ohm  resistance  by  a  difference 
of  potential  of  one  volt.  Its  value  is  1-10  that  of  the  C.  G.  S. 
or  absolute  unit  of  strength. 

Amperemeter.— A  mechanism  for  measuring  the  current 
strength,  or  flow  of  the  current. 

Anions— The  products  of  electrolysis  which  appear  at  the 
anode. 

Anode— The  electrode  in  connection  with  the  pole  (metal, 
platinum,  carbon,  etc.)  of  the  battery  or  cell. 

Annunciators— An  electric  mechanism  for  calling  or 
signalling  purposes. 

Arc  L«ight— The  light  produced  by  the  electric  current 
at  the  ends  of  two  carbon  sticks  placed  in  easy  contact. 
The  friction  engendered  by  the  short  leap  of  the  current 
heats  the  carbon  points  to  a  temperature  of  from  five  thou- 
sand to  eight  thousand  degrees,  thus  causing  them  to  give  off 
a  brilliant  light.  The  bombardment  of  the  carbon  particles 
intensifies  the  heat  and  really  adds  to  the  whiteness  of  the 
light.  The  pure  electric  arc  is  of  a  violet  blue  color  and  not 
white.  The  positive  carbon,  or  the  one  from  which  the  cur- 
rent leaps  to  cross  the  break  is  heated  to  a  higher  degree 
than  the  negative,,  or  lower  carbon,  which  receives  the  cur- 
rent, and  is  consumed  more  rapidly.  It  burns  down  in  the 
ordinary  arc  light  about  one-and-a-half  inches  per  hour,  while 
the  negative  carbon  is  consumed  at  about  half  that  rate. 


AND  EXPLANATIONS.  239 

Armature— The  revolving  fixture  of  the  dynamo,  consist- 
ing of  a  core  of  iron,  wrapped  with  coils  of  copper  wire 
which  revolves  rapidly  between  the  poles  of  the  magnet,  but 
does  not  touch  these  poles.  The  current  produced  flows  in 
opposite  directions  as  th.ey  pass  the  poles  in  succession,  but 
by  means  of  the  commutator  they  are  made  to  flow  in  one 
and  the  same  direction. 

Armature  Core— The  soft  iron  portion  or  core  of  the 
armature. 

Artificial  Magnets— Bodies  in  which  magnetism  is  arti- 
ficially induced. 

Attraction  and  Repulsion— Properties  of  the  magnet 
and  electro-magnet.  Like  poles  repel  and  unlike,  attract. 
The  intensity  of  this  attraction  or  repulsion  varies  in  the 
inverse  ratio  of  the  square  of  the  distance;  that  is,  if  the 
distance  of  the  pole  is  doubled,  the  force  with  which  they 
attract  or  repel  each  other  is  reduced  to  one-quarter  of  the 
previous  amount;  if  trebled,  to  one-ninth,  and  so  on.  This 
attraction  and  repulsion  which  so  signally  characterizes  the 
magnet,  is  the  foundation  and  essential  factor  in  nearly  all 
forms  of  electrical  mechanism. 

Automatic— Self-operating;  electricity  is  prolific  in  auto- 
matic mechanism. 

Axial  lane— The  line  joining  the  poles;  the  lines  at  right 
angles' to  it  is  called  the  equatorial. 

B.  A.  Unit— The  standard  fixed  upon  by  the  British 
Association  as  the  unit  of  electrical  resistance,  and  is  the  same 
as  the  ohm.  It  is  approximately  equal  to  in  resistance  to  a 
wire  of  pure  copper  250  feet  long,  and  the  one  twentieth  of 
an  inch  in  diameter. 

Bar  Magnet— An  artificial  permanent  magnet  in  the  form 
of  a  straight  bar;  a  magnet  composed  of  several  straight 


240  ELECTRICAL  DICTIONARY 

bars  joined  together,  side  by  side,  is  called  a  compound  bar 
magnet. 

Battery— One  or  more  cells  which  are  provided  with  the 
proper  solution  and  plates,  connected  together,  which  gen- 
erates electricity  by  chemical  action. 

Bec-Carcel— The  French  unit  of  light,  taken  from  the 
light  of  a  Carcel  lamp,  and  is  equal  to  9.5  British  standard 
candles,  or  7.6  German  candles. 

Brake-Shoes—Electric  brakes  for  operating  electric  mo- 
tors, etc. 

Break.— A  complete  disconnection,  which  occurs  when 
the  circuit  is  open.  It  may  be  caused  by  a  broken  ground 
wire,  defective  battery,  open  key,  broken  line  wire,  etc. 

Calorie— The  unit  of  heat,  which  in  the  C.  G.  S.  system 
is  the  gramme  degree.  Its  mechanical  equivalent  is  equal  to 
42,000,000  ergs  (the  unit  of  work.) 

Candle  Power— The  British  unit  of  light  is  the  light 
of  a  spermaceti  candle  £  of  an  inch  in  diameter,  burning  120 
grains  per  hour  (six  candles  weigh  one  pound);  the  German 
unit  is  the  light  of  a  paraffine  candle  20  millimeters  in  diame- 
ter, burning  with  a  flame  five  centimeters  high. 

Carbons.— The  "  sticks "  used  in  the  carbon  arc  light 
lamp.  They  are  made  of  powdered  cake  15  parts,  lamp 
black  4  parts,  and  special  syrup  8  parts,  mixed  with  water 
and  molded  and  dried  in  a  crucible. 

Cathode— The  electrode  in  connection  with  pole  (  metal, 
zinc,  etc. )  of  the  cell  or  battery. 

Cations— The  products  of  electrolysis  which  appear  at 
the  cathode. 

Centimeter— The  fundamental  unit  of  length;  equal  to 
0.3937  inch  in  length,  and  nominally  represents  the  one 
thousand-millionth  part  of  a  quadrant  of  the  earth. 


AND  EXPLANATIONS.  241 

Circular  Mil— The  practical  unit  of  wire  gauge,  which 
is  a  wire  the  one-thousandth  of  an  inch  in  diameter,  usually 
written  as  so  many  mils. 

Closed  Circuit.— A  complete  circuit;  connected  and  un- 
broken, so  that  the  electric  energy  "  flows"  all  around,  which 
it  could  not  do  if  the  line  were  broken. 

Commutator— An  instrument  whose  use  is  to  change 
the  direction  in  which  the  current  flows  through  the  primary 
circuit,  and,  of  necessity,  to  change  the  direction  of  that  in 
the  secondary  circuit  also. 

Condenser — An  instrument  to  add  to  the  current  travers- 
ing the  primary  wire,  and  consequently  to  increase  the  force 
of  the  secondary  discharge.  It  consists  of  a  number  of 
plates  of  tin-foil,  separated  by  sheets  of  varnished  or  rosin- 
ized  paper;  the  alternate  tin-foil  plates  being  attached  to- 
gether, thus  forming  two  separate  insulated  series.  One 
series  of  the  plates  is  connected  with  the  pillar  of  the  con- 
tact-breaker that  carries  the  platinum  screw,  and  the  other 
series  with  the  block  that  holds  the  vibrating  spring.  These 
plates  do  not  form  a  part  of  the  battery  circuit,  but  are,  as  it 
were,  lateral  expansions  of  that  circuit,  on  each  side  of  the 
contact-breaker.  The  insulating  sheets  thus  have  their  elec- 
trical condition  disturbed,  and  when  the  battery  is  inter- 
rupted the  plates  return  to  their  normal  state,  and  in  so  do- 
ing increase  the  action  of  current  circulating  in  the  primary 
wire. 

Conductors— Substances  that  possess  the  property  of  al- 
lowing electricity  to  diffuse  itself  freely  and  readily  through 
them. 

Constant  of  a  Galvanometer— The  deflection  of  the 
galvanometer,  obtained  through  a  standard  resistance  by  a 
standard  battery.  As  explained  by  Kempe,  it  is  the  "prod- 


242  ELECTRICAL  DICTIONARY 

uct  of  the  deflection  in   degrees  and  the  resistance  in  ohms 
when  multiplied  together." 

Contact-Breaker— A  vibrator  by  which  the  electric  cur- 
rent can  be  made  and  broken  with  great  rapidity. 

Crater— A  term  used  to  express  the  hollowing  out  of  the 
upper  (positive)  carbon  in  the  arc  lamp.  The  upper  carbon 
burns  hollow,  and  the  lower,  cone  shape. 

Cross— Where  one  wire  crosses  another  and  interferes 
with  the  line,  often  caused  by  wind,  branches  of  trees,  etc. 

Dead  Earth.— A  term  used  when  the  line  at  any  point 
touches  the  ground,  or  some  good  conductor  in  contact  with 
the  earth.  This  is  also  called  a  "  ground." 

Diamagetic — Substances  which  are  repelled  by  the  mag- 
net. Bismuth,  antimony,  zinc,  etc.,  are  diamagnetic.  It  is 
found  that  the  magnetism  of  two  iron  particles  lying  in  the 
line  of  magnetization  is  increased  by  their  mutual  action, 
but  on  the  contrary,  the  diamagnetism  of  two  bismuth  par- 
ticles lying  in -this  direction  is  diminished  by  their  mutual 
actions.  . 

Dielectric— The  insulating  substance  which  separates 
two  conducting  surfaces  and  thereby  enables  them  to  sustain 
opposite  electrical  states.  All  insulators  are  dielectrics. 

Dip— The  "  dip  "  of  any  telegraph  line  wire  is  the  sag  be- 
tween the  poles;  the  dip  of  the  magnetic  needle  is  the  ver- 
tical angle  of  the  needle  with  the  horizon;  the  tendency  to 
point  downwards. 

Difference  of  Potential— The  difference  of  potential 
between  any  two  points  expresses  the  amount  of  work  which 
each  unit  of  electricity  could  do  on  its  journey  if  it  could 
all  be  utilized  to  do  work  instead  of  having  to  overcome  the 
resistance  of  the  circuit.  -The  place  from  which  the  positive 


AND  EXPLANATIONS.  243 

electricity  tends  to  move  is  assumed  to  be  of  higher  poten- 
tial than  the  other. 

Duplex  Telegraphy— Sending  two  messages  over  the 
same  wire  at  the  same  time. 

Dynamo — A  machine  for  converting  mechanical  into  elec- 
tric energy;  or  a  machine  that  generates  electricity.  When 
a  piece  of  soft  iron  is  brought  near  a  magnet,  it,  too,  be- 
comes a  magnet.  If,  for  instance,  a  common  nail  has  its 
point  brought  near  the  north  pole  of  a  magnet,  the  head  of 
the  nail  will  at  once  become  a  north  pole  and  its  point  a 
south  pole.  If  the  position  of  the  hail  is  reversed,  the 
magnetism  will  remain  the  same  as  relates  to  the  magnet, 
but  not  to  the  nail.  The  nail  may  be  said  to  have  turned 
round  on  its  magnetism.  If,  now,  this  nail  should  have  a 
small  shaft  through  it  perpendicular  to  its  axis,  and  mounted 
so  as  to  be  revolved  with  rapidity  while  in  this  position, 
the  magnetism  in  the  nail  would  change  at  each  turn,  the 
end  nearest  the  magnet  always  being  a  south  pole.  This  is 
called  a  change  of  polarity.  Now,  if  on  this  nail  a  fine  coil 
of  insulated  wire  be  placed,  and  the  outside  and  inside  ends 
connected  together,  a  strong  pulsation  of  electricity  will 
take  place  in  the  wire  of  the  coil  at  each  half  turn.  When 
the  ends  of  the  wire  are  separated  and  brought  down  to  the 
shaft,  so  that  the  current  may  be  taken  off  through  a  com- 
mutator, or  stationary  conductor,  we  have  a  complete  little 
dynamo,  which  only  needs  enlarging  to  produce  an  electric 
light.  The  effect,  however,  would  be  very  much  increased 
if  we  bent  the  nail  in  the  form  of  a  ring,  with  a  shaft  se- 
cured into  it  like  the  shaft  in  a  wheelbaiTow  wheel,  and  the 
coil  divided  up  into  twenty  or  more  sections,  each  section 
ending  in  an  independent  copper  strip  in  the  commutator. 
Another  improvement  would  result  from  revolving  it  be- 
tween two  magnets  of  opposite  polarity,  or  between  the  op 


244  ELECTRICAL  DICTIONARY 

posite  poles  of  a  horse-shoe  magnet.  It  will  be  seen  the  mag- 
netic principle  of  attraction  and  repulsion  is  the  essential- 
factor  of  the  dynamo. 

Dyne — The  unit  of  force;  called  the  absolute  unit,  and 
also  the  C.  G.  S.  unit. 

Electric  Bells— Bells  rung  by  the  electric  current. 
There  are  "  single  stroke,"  "  vibrating  or  trembling,"  and 
other  kinds  of  electric  bells,  manipulated  by  push  buttons, 
cranks,  etc.,  and  all  operating  upon  the  principle  of  making 
and  breaking  the  circuit,  or  the  action  of  the  electro-magnet. 

Electric  Candle— Where  two  carbon  sticks  are  placed 
upright,  parallel  to  each  other  and  separated  by  a  thin  in- 
sulator, and  which  burn  from  the  top  down  like  a  candle; 
an  invention  of  Jablochkoff,  in  1876. 

Electric  Circuit.— The  entire  path  of  the  electric  cur- 
rent, including  the  battery  itself  and  the  conducting  medium 
which  unites  its  poles. 

Electric  Current— A  current  of  electric  fluid  traversing 
a  closed  circuit  over  conductors,  or  passing  by  means  of  con- 
ductors from  one  body  to  another  which  is  in  a  different 
electrical  state.  Its  symbol  is  C.  Machines  are  constructed 
to  give  continuous  currents  and  alternating  currents. 

Electricity— "  A  form  of  motion;  energy  charged  in  a 
special  manner  upon  ordinary  matter  and  developing  special 
relations  among  its  molecules.  It  is  not  material,  or  fluid, 
nor  is  it  a  special  force."  (Sprague.)  It  is,  however,  treated 
as  if  it  were  a  fluid,  because  it  is  more  easily  understood 
when  so  considered;  hence  we  speak  of  the  "flow  of  cur- 
rent," etc.  The  fluid  theory  was  held  by  nearly  all  the 
older  electricians,  and  even  to-day  we  cannot  talk  or  write 
about  it  in  a  manner  to  be  comprehended  except  as  we  treat 
it  as  a  fluid  having  current,  etc.;  and  to  all  intents  and  pur- 


AND  EXPLANATIONS.  245 

poses  it  acts  as  if  it  were  a  fluid.  According  to  the  fluid 
theory,  there  were  two  kinds  of  fluids,  each  very  subtle,  rare, 
quite  imponderable,  and  consisting  of  particles  that  repel 
each  other.  Benjamin  Franklin  believed  in  only  one  fluid, 
the  particles  of  which  mutually  repel  each  other.  What  was 
called  vitreous  electricity,  Franklin  called  positive  electricity, 
and  the  resinous  he  called  negative.  Professor  Pepper  of 
the  Royal  Polytechnic  Institute,  London,  said  long  ago  that 
"  the  same  wave  theory  which  accounts  for  heat  and  light 
will  doubtless  ultimately  be  applied  to  electricity,  which  may 
be  only  some  remarkable  vibratory  state  of  the  ether  per- 
vading all  matter  and  space;"  "and  this  opinion,"  he  adds, 
"  was  held  forty  years  before  Galvani,  by  Sultzer,  who  first 
experimented  with  pieces  of  silver  and  lead.  By  placing 
them  on  opposite  sides  of  the  tongue,  and  then  bringing  the 
two  in  contact,  he  noticed  a  peculiar  metallic  taste,  like 
vitriol."  The  American  school  of  electricians,  which  is  de- 
cidedly practical  in  its  ideas,  perhaps  more  generally  consid- 
ers electricity  a  "  form  of  energy  "  having  its  peculiar  attri- 
butes, back  of  which  they  have  not  as  yet  cared  to  go.  As  a 
matter  of  fact,  electricity  is  evolved  in  any  disturbance  of 
molecular  equilibrium,  whether  from  a  chemical,  physical  or 
mechanical  cause.  Lockwood  defines  electricity  as  "  one  of 
those  peculiar  forces  of  nature  as  universal  in  its  effects  as 
its  kindred  forces,  light  and  heat,  and  is  in  many  respects 
analogous  to  them.  Scientists,  at  present,  consider  elec- 
tricity to  be  a  particular  form  of  energy  which  causes  the 
infinitesimal  particles  to  alter  their  positions  in  regard  to  one 
another." 

Electro-Chronograph— A  mechanism  for  noting  time 
by  means  of  electricity;  an  electric  clock. 

Electrodes— The  terminals  of  the  poles  of  the  battery 
or  cell  which  excite  the  current,  and  which  are  in  contact 
with  the  electrolyte  or  solution. 


246  ELECTRICAL  DICTIONARY 

Electro-Dynamics.— Having  reference  to  electricity  in 
motion.  Its  phenomena  as  classified  by  Faraday  are:  Evo- 
lution of  heat,  magnetism,  chemical  decomposition  ( elec- 
trolysis), physiological  phenomena  and  the  spark. 

Electrolysis— The  decomposition  of  bodies  by  means  of 
the  electrical  current,  their  elements  being  set  free. 

Electrolytes— Bodies  that  may  be  decomposed  directly 
by  the  electric  current,  their  elements  being  set  free. 

Electrolyzation— The  process  of  decomposition  by  means 
of  an  electric  current. 

Electro-Magnet— A  mass  of  so/t  iron,  usually  in  the 
form  of  a  bar,  rendered  temporarily  magnetic  by  being  placed 
within  a  coil  of  wire  through  which  a  current  of  electricity 
is  passing. 

Electro-Magnetism— Magnetism  produced  by  means  of 
electricity. 

Electrometer— A  mechanism  for  measuring  the  quan- 
tity or  intensity  of  electricity.. 

Electro-motive  Force— The  force,  or  pressure,  which 
electric  energy  is  capable  of  exerting  by  virtue  of  a  differ- 
ence of  electric  potential  between  the  body  in  which  it  is 
accumulated  and  some  other  body.  It  is  also  defined  as  "  the 
force  which  sets  the  current  moving  around  a  closed  circuit," 
and  is  often  called  the  "  electrical  pressure"  As  with  water, 
the  higher  the  level  the  greater  is  the  pressure  and  power,  so 
with  electricity,  the  higher  the  electric  level  or  potential  the 
greater  the  pressure,  or  electro-motive  force.  The  force  or 
pressure  is  exerted  by  the  energy  itself,  the  body  in  which 
it  is  accumulated,  or  by  which  it  is  transmitted,  being  only  a 
passive  medium.  It  is  a  very  singular  fact  that  a  loose,  dang- 
ling wire  will  conduct  from  a  dynamo  a  force  which  at  the 


AND  EXPLANATIONS.  247 

distant  end,  miles  away,  will  run  a  motor  of  many  horse 
power.  The  question  is,  What  is  this  subtle  influence  that 
so  occultly  and  curiously  operates?  We  may  define,  but  alas, 
no  one  can  yet  explain.  Let  us  hope  that  "  Time  will  tell." 
The  symbol  of  electro-motive  force  is  E.  M.  F.,  sometimes 
written  only  E.,  and  its  practical  unit  is  the  "  volt,"  which  is 
100,000,000  "absolute,"  or  C.  G.  S.  units.  The  E.  M.  F.  of 
a  Daniell  cell  is  about  one  volt. 

Electroscope— An  instrument  for  showing  electrical  ex- 
citation, or  the  presence  of  electricity,  the  simplest  being 
that  of  two  delicately  suspended  pith  balls. 

Electrophorns— A  mechanism  for  exciting  electricity 
and  repeating  the  charge  indefinitely  by  induction. 

Electroplate— The  process  of  covering  with  a  coat  of 
metal  by  means  of  electrolysis. 

Electro-positive— Of  such  a  nature  relative  to  some 
other  associated  body  or  bodies  as  to  tend  to  the  negative 
pole  of  a  voltaic  battery,  while  the  associated  body  tends  to 
the  positive  pole.  The  converse  of  this  is  the  electro  nega- 
tive. 

Electro-statics— That  which  pertains  to  statical  elec- 
tricity. 

Electro-therapeutics— Electricity  in  relation  to  disease; 
now  recognized  as  a  valuable  element  in  the  healing  art. 

Electro-tint— Etching  by  means  of  electricity;  where  a 
picture  is  drawn  on  a  metallic  plate  with  some  materials 
that  resist  the  fluids  of  the  battery,  so  that  in  electrotyping, 
the  parts  not  covered  by  the  varnish  receive  a  deposition  of 
metal  and  produce  the  required  copy  in  intaglio. 

Electrotype — The  process  of  copying  metals,  engravings, 
etc.,  and  of  making  stereotype  plates  by  means  of  electric 


248  ELECTRICAL  DICTIONARY 

deposition;  or  the  art  of  producing  copies  in  metal  of  any 
object  by  means  of  the  action  of  electricity.  Engravings, 
book  pages  set  in  type,  and  composition  work  generally,  may 
be  accurately  and  permanently  copied  by  this  process  with  a 
metal  surface,  which  is  usually  copper.  This  art  was  intro- 
duced in  1838,  by  Prof.  Jacobi,  of  St.  Petersburg,  and  also, 
about  the  same  time,  by  Thomas  Spencer,  of  Liverpool,  who 
demonstrated  its  practical  utility.  A  printer  by  the  name  of 
Jordan  also  aided  in  its  development. 

E.  M.  F.— Is  said  to  "  signify  that  property  of  any  source 
of  electricity  by  which  it  tends  to  do  work  by  transferring 
electricity  from  one  point  to  another."  The  E.  M.  F.  of  a 
battery  is  the  power  which  it  has  of  overcoming  resistance. 
It  increases  in  direct  proportion  to  the  number  of  cells  em- 
ployed. It  is  often  written  with  only  an  E.  instead  of 
E.  M.  F.  which  letters  indicate  Electro-Motive  Force. 

Energy— A  body  is  said  to  possess  energy  when  it  is  ca- 
pable of  doing  work,  either  in  consequence  of  the  motion 
with  which  it  is  endowed  or  its  position.  A  ball  fired  up- 
ward possesses  the  power  of  doing  work  on  account  of  its 
motion.  This  energy  from  motion  is  called  Kinetic  energy. 
At  the  top  of  its  flight  the  energy  of  the  ball  is  not  lost,  but 
is  transformed.  The  ball  now  has  energy  due  its  position, 
and  will  be  able  to  do  the  same  work  in  falling  as  in  rising. 
As  long  as  the  ball  is  supported  in  its  elevated  position  its 
energy  is  potential,  and  may  be  called  upon  to  do  its  work 
when  desired.  Thus  the  separated  elements  of  a  chemical 
compound  just  as  truly  possess  energy  of  position  as  an  ele- 
vated body.  Allow  them  to  unite  and  their  potential 
energy  passes  into  Kinetic  energy,  and  the  work  of  separation 
is  returned  in  that  of  chemical  combination.  What  the 
projected  ball  loses  in  Kinetic  energy,  it  has  gained  exactly 
in  potential  energy.  Considering  the  universe  as  a  whole, 


AND  EXPLANATIONS.  249 

we  find  a  like  condition  of  things.  The  sum  of  the  energy 
due  to  the  position  of  things  is  always  equal  to  the  sum  of 
the  energy  due  to  motion.  This  is  the  "  conservation  of 
energy,"  or,  as  it  is  often  called,  "  the  conservation  of  the 
forces." 

Erg— The  unit  of  work  (adopted  by  the  Paris  Congress.) 
There  is  in  one  foot-pound  13,563,000  ergs;  and  in  one  Eng- 
lish horse-power,  7,460,000,000  ergs.  The  unit  of  work  is 
therefore  the  1-13,563,000  of  a  foot-pound. 

Escape — The  loss  of  a  portion  of  the  current  on  the  main 
line  is  called  an  "  escape,"  caused  by  defective  insulation,  etc. 

Farad— The  practical  unit  of  capacity,  named  in  honor 
of  the  celebrated  Faraday.  The  capacity  is  determined  by 
dividing  the  quantity  of  the  charge  by  its  potential.  This 
unit  is  equal  to  1-1 0'9  of  the  C.  G.  S.  unit  of  capacity.  As 
this  is  large,  the  microfarad  is  commonly  used  in  practice, 
which  is  the  one  millionth  part  of  a  farad. 

Ferro-magnetic— Iron  and  similar  bodies  which  are 
attracted  by  the  magnet. 

Foot-pound— The  work  required  to  raise  one  pound  one 
foot. 

Force— That  which  produces  motion  or  change  of  motion 
in  a  body.  The  unit  of  force  is  that  force  which,  acting  for 
one  second  on  a  mass  of  one  gramme,  gives  to  it  a  velocity 
of  one  centimeter  per  second.  This  is  the  "  absolute  unit." 

Galvanic  Battery— Two  dissimilar  substances  or  metal- 
lic surfaces,  both  being  conductors  of  electricity,  immersed 
in  a  jar  of  acidulated  water  or  other  exciting  fluid  that  will 
act  more  energetically  on  one  than  the  other,  and  connected 
on  the  outside  with  a  wire.  The  materials  most  suitable  are 
carbon,  platinum,  gold,  silver,  copper,  iron,  tin,  lead,  zincj 


250  ELECTRICAL  DICTIONARY 

and  the  exciting  fluids  are  sulphuric  and  nitric  acids,  bi-chro- 
mate  of  potash,  sulphate  of  copper,  etc.  The  ordinary  bat- 
tery is  made  with  copper  and  zinc  plates  inserted  in  a  jar 
filled  with  sulphuric  acid,  the  plates  being  connected  by  a 
wire,  which  forms  the  circuit  of  current.  It  is  the  chemical 
action  in  connection  with  the  plates  that  generates  the  elec- 
tricity. 

Galvanometer— An  instrument  for  indicating  or  meas. 
uring  the  quantity  of  electricity,  and  for  detecting,  indicat- 
ing or  measuring  the  currents  of  electricity.  The  principle 
is  that  of  attraction  and  repulsion  produced  by  the  current 
on  a  magnet  that  carries  a  little  mirror  which  reflects  a  lamp 
light  ray  on  a  screen  or  dial.  Of  course,  the  slightest  cur- 
rent will  move  the  magnet,  and  the  slightest  movement  of 
the  magnet  and  mirror  throws  the  reflected  ray  backward  or 
forward  on  the  screen. 

Gastroscope— An  electric  apparatus  used  by  physicians 
for  exploring  the  interior  of  the  stomach.  A  little  incandesc- 
ent lamp  is  adjusted  and  inserted  and  then  the  current 
turned  on. 

Gramme— The  fundamental  unit  of  mass,  and  is  equal  to 
15.432  grains,  and  represents  the  mass  of  a  cubic  centi- 
meter of  water  at  4°  C.  Mass  is  the  quantity  of  matter  in 
a  body. 

Ground  Wire— The  terminal  wire  of  a  line  that  may 
run  into  the  ground  or  be  attached  to  gas  or  water  pipes, 
etc.,  and  to  which  also  are  attached  the  lightening  arresters. 
They  are  also  used,  when  the  line  is  impaired  or  broken,  for 
testing  to  ascertain  the  point  of  current  interruption. 

Horse-power— The  power  required  to  raise  650  Ibs.  one 
foot  high  in  one  second,  or  33,000  Ibs-  in  one  minute. 

Horse-shoe  Magnet— A  permanent  magnet  bent  in  the 


AND  EXPLANATIONS.  251 

form  of  the  letter  U,  which  brings  the  two  opposite  poles 
near  together. 

Incandescent— That  which  is  heated  to  a  white  heat. 

Incandescent  tight— The  light  produced  by  the  elec- 
tric current  overcoming  the  resistance  offered  by  a  filament 
of  carbon,  and  raising  it  to  a  temperature  sufficient  to  render 
it  luminous.  This  filament  is  placed  in  a  glass  bulb  from 
which  the  air  has  been  exhausted,  and  therefore  cannot  burn. 
In  fact,  the  carbon  filament  of  the  incandescent  light  is  sim- 
ply heated  to  a  white  heat  by  the  current  in  a  vacuum. 

Induction  of  Electricity— Developing  electricity  in  a 
body  by  the  influence  of  other  electricity  in  its  neighborhood. 

Indnction  of  Magnetism— Developing  magnetic  prop- 
erties in  a  body  by  the  influence  of  a  magnet. 

Insulation. — Prevention  of  the  escape  of  electricity; 
glass,  ebonite  and  silk  are  among  the  insulating  substances. 

Insulators.— Substances  that  do  not  allow  electricity  to 
diffuse  itself  through  them. 

Intensity  of  Magnetization.— The  intensity  of  mag- 
netization of  a  magnetic  particle  is  the  ratio  of  its  magnetic 
movement  to  its  volume. 

Intermittent  Cross.— Where  the  wires  are  too  slack 
between  the  poles  so  that  they  often  touch  each  other  and 
interfere  with  sending  of  messages. 

Joint  Resistance. — The  resistance  of  two  or  more  inde- 
pendent branches  of  a  circuit  considered  and  treated  as  one. 

Jomle— The  electrical  unit  of  work,  as  proposed  by  Sir 
William  Siemens.  It  is  equivalent  to  the  volt-coulomb,  and 
to  107  ergs.  It  represents  the  work  done  in  one  second  in 
a  circuit  of  one  ohm  resistance  by  a  current  of  one  ampere. 


252  ELECTRICAL  DICTIONARY 

Kinetie  Energy— The  work  a  body  can  do  by  virtue  of 
its  motion. 

Leclanche  Battery— A  popular  electric  battery  using 
zinc  and  carbon  plates,  and  a  solution  of  salamoniac. 

JLeyden  Jar— A  device  for  the  accumulation  of  electricity, 
consisting  of  a  glass  jar  coated  inside  and  outside  with  tin- 
foil, except  a  few  inches  at  the  top. 

Local  Action— The  name  given  to  the  chemical  action  in 
the  battery,  whether  the  circuit  is  closed  or  open. 

IJoop— A  wire  which  branches  out  from  the  main  line  to 
some  other  point  and  returns  to  the  main  line  again  at  or 
near  the  point  where  it  left  it. 

Magnet— A  body  that  exhibits  magnetic  properties,  such 
as  attraction,  repulsion,  polarity,  etc. 

Magnetic  Induction— See  Induction  of  Magnetism. 

Magnetic  Moment— The  product  of  the  length  of  a 
uniformly  and  longitudinally  magnetized  bar  magnet  into  the 
strength  of  its  positive  pole. 

Magnetic  Needle— A  light  and  slender  magnet  mounted 
upon  a  center  of  motion  so  as  to  allow  it  to  traverse  freely. 

Magnetic  Polarization— In  speaking  of  the  state  of 
the  particles  of  a  magnet  as  magnetic  polarization,  we  imply 
that  each  of  the  smallest  parts  into  which  a  magnet  may  be 
divided  has  certain  properties  related  to  a  definite  direction 
through  the  particle,  called  its  axis  of  magnetization,  and 
that  the  properties  related  to  one  end  of  this  axis  are  op- 
posite to  the  properties  related  to  the  other  end.  The  prop- 
erties which  we  attribute  to  the  particle  are  the  same  kind 
which  we  observe  in  the  complete  magnet.  In  other  words, 
each  particle  is  a  perfect  magnet;  their  poles  all  point  in  the 
same  way,  i  e.,  in  a  line  of  the  axis  of  magnetization. 


AND  EXPLANATIONS.  253 

Magnetism— The  peculiar  properties  of  attraction,  repul- 
sion, polarity  and  induction  possessed  under  certain  conditions 
by  iron  and  some  of  its  compounds;  also  nickel,  cobalt,  etc 
The  name  is  supposed  to  be  derived  from  Magesia,  the  place 
where  lodestone  (the  natural  magnet)  was  first  found  by  the 
Greeks. 

Magneto  Bell— A  polarized  relay,  with  its  armature  ex- 
tended into  a  hammer  which  vibrates  between  two  bells. 

Magneto-Electricity—Electricity  produced  by  the  in- 
fluence of  magnetism. 

Magnetometer— An  instrument  for  measuring  the  mag- 
netizing power  of  galvanic  currents. 

Mass — The  quantity  of  matter  in  a  body. 
Megafarad— One  million  farads. 
Mega  volt— One  million  volts. 
Megohm— One  million  ohms. 

Metronome— An  instrument  which  serves  to  measure 
time  in  music. 

Microfarad— One  millionth  of  a  farad. 
Microvolt— One  millionth  of  a  volt. 
Microhm— One  millionth  of  an  ohm. 

Microphone — An  electrical  instrument  by  which  minute 
sounds,  like  those  of  a  fly  walking,  may  be  magnified  so  as 
to  be  distinctly  audible.  Its  action  is  due  to  the  disturbance 
of  electric  contacts,  and  in  reality  it  is  a  form  of  a  tele- 
phone transmitter. 

Mil— One  thousandth  of  an  inch. 

Milli-ampere— The  thousandth  part  of  an  ampere.  The 
electric  currents  employed  in  telegraphy  vary  from  4  to  250 


254  ELECTRICAL  DICTIONARY 

inilli-amperes,  the  latter  being  the  approximate  current 
strength  flowing  in  an  ordinary  local  sounder  circuit;  cur- 
rents utilized  in  electric  lighting  vary  between  one  and  fifty 
amperes. 

Momentum— The  quantity  of  motion  in  a  body,  which  is 
measured  by  the  product  of  the  velocity  of  the  body  into  the 
mass. 

Motor— A  machine  for  converting  electrical  into  mechan- 
ical energy.  All  electric  motors  owe  their  motion  to  the 
attractions  and  repulsions  caused  by  the  actions  of  electro- 
magnets. 

Multiplex  Telegraphy— Sending  a  number  of  mes- 
sages over  the  same  wire  at  the  same  time. 

Natural  Magnets— Lodestones  (a  certain  kind  of  iron- 
ore.) 

Non-Conductors—Substances  that  do  not  allow  elec- 
tricity to  pass  through  them;  such  as  glass,  gutta-percha, 
ebonite,  etc.,  and  which  therefore  are  used  in  making  insula- 
tors. Dry  air  and  ebonite  are  among  the  best  non-conduc- 
tors, and  silver  is  the  best  conductor. 

Ohm— The  practical  electric  unit  of  resistance,  named  in 
honor  of  Ohm,  who  first  suggested  the  method  of  measur- 
ing electrical  resistance.  It  is  equal  to  109  C.  G.  S.  or  ab- 
solute units,  or  the  resistance  of  a  pure  copper  wire  one  milli- 
meter in  diameter  and  forty-eight  meters  long.  "  Roughly 
speaking,"  says  Prescott,  "  one  thousand  ohms  is  equal  to 
seventy  miles  of  well  constructed  line."  The  ohm  has  been 
derived  from  the  relation  between  a  current,  the  mechanical 
force  it  exerts  on  a  magnet,  the  distance  of  the  magnet,  and 
its  strength. 

Ohms  I^aw— «  Current  :=  Eiect^yioge^orce  or  Q:=  _|.  » 
Ohms  Law  was  promulgated  by  Dr.  G.  S.  Ohm  of  Nuremberg, 


AND  EXPLANATIONS.  255 

Germany,  as  early  as  1827,  and  is  the  basis  of  all  electrical 
measurements.  According  to  this  law  we  have  the  E.  M.  F. 
divided  by  the  resistance,  giving  us  the  current  strength; 
therefore  the  resistance  equals  the  E.  M.  F.  divided  by  the 
current,  and  the  E.  M.  F.  equals  the  current  multiplied  by 
the  resistance. 

Paramagnetic  — Magnetic;  opposed  to  diamagnetic. 
Bodies  which  are  repelled  by  the  magnet,  such  as  bismuth, 
antimony,  lead,  tin,  mercury,  gold,  silver,  zinc,  copper,  water, 
sulphur,  sugar,  etc.,  are  diamagnetic;  but  iron,  nickel,  cobalt, 
chromium,  manganese,  platinum,  etc.,  are  attracted  by  the 
magnet  and  are  called  magnetic,  or  paramagnetic. 

Permanent  Magnet— A  magnet  formed  of  hardened 
steel  that  retains  its  magnetic  properties. 

Photometer— An  instrument  for  measuring  the  intensity 
of  light.  In  Rumford's  photometer  the  shadows  of  an 
opaque  rod  are  thrown  from  the  two  lights  and  compared  on 
a  white  screen. 

Photometry— Measuring  light.  The  intensity  of  light 
on  unit  surface  is  inversely  as  the  square  of  the  distance 
from  the  source. 

Photophore— A  peculiar  form  of  an  incandescent  lamp 
used  by  physicians  in  exploring  the  cavities  of  the  ear,  nose, 
larynx,  etc. 

Ping  Switch— Two  or  more  brass  plates,  with  holes  drilled 
between  them,  so  that  by  the  insertion  of  a  metal  plug  any 
two  or  more  plates,  with  the  circuits  attached  to  them,  may 
be  connected  together. 

Polarity — The  directive  force  of  a  magnet,  which 
always  comes  to  rest  with  the  same  pole  pointing  north. 

Polarization— The  electric  re-action  at  the  poles  of  a 


256  ELECTRICAL  DICTIONARY 

cell,  and  is  of  the  nature  of  a  counter  electro-motive  force. 
It  is  in  overcoming  this  polarization  force  that  we  are 
enabled  to  store  electricity. 

Poles— The  extremities  of  a  magnet;  one  of  which  is 
called  the  north  pole,  because  it  points  north,  and  the  other 
the  south  pole,  the  symbols  of  which  are  N.  and  S. 

Poles  of  a  Battery— Terms  applied  to  that  part  of  the 
plates  that  is  without  the  exciting  fluid  of  a  battery,  i.  e.,  not 
immersed  in  it;  one  of  which  is  positive,  and  the  other  nega- 
tive. The  immersed  portions  of  the  plates  are  the  positive 
and  negative  elements  of  a  battery,  and  they  are  always  the 
reverse  of  the  poles,  so  that  each  plate  of  a  battery  has  oppo- 
site terms  applied  to  it,  one  part  being  called  positive,  and 
the  other  negative,  as  it  is  in,  or  out  of,  the  acid  solution. 
The  binding  screws  and  wire  attachments  are  included  as  a 
part  of  the  plate  outside  of  the  liquid.  In  a  zinc  and  copper 
battery  the  zinc  in  the  solution  is  the  positive  plate,  but  the 
wire  leading  from  it  is  the  negative  pole,  while  the  copper  is 
the  negative  plate,  but  the  wire  proceeding  from  it  is  the 
positive  pole.  The  electric  action  begins  at  the  zinc  plate, 
passes  through  the  liquid  to  the  copper  plate  and  out  of  the 
liquid,  and  thence  over  the  wire  and  back  to  the  zinc  plate. 

Potential  —  A  term  used  to  represent  the  energy  which 
a  body  may  possess  to  do  work.  Thus  a  weight  has  gravity 
potential;  a  furnace  has  heat  potential;  and  electricity  in  this 
manner  is  said  to  have  electric  potential.  A  difference  of 
potential  is  analogous  to  a  difference  of  level  of  water,  and 
just  as  work  must  be  done  in  raising  water  from  the  lower  to 
the  higher  level,  so  work  must  be  done  in  raising  electricity 
from  the  lower  to  the  higher  electric  level.  The  water,  in 
falling,  is  able  to  perform  the  work  done  in  lifting  it,  and  so 
the  electricity  is  able  to  do  that  which  was  done  in  raising  it 
to  the  higher  potential.  The  greater  the  difference  in  water 


AND  EXPLANATIONS.  257 

level,  the  greater  is  the  "head"  of  water  and  the  water 
power;  and  the  greater  the  difference  of  electric  potential, 
the  greater  is  the  electric  energy.  And  just  as  water  cannot 
flow  "  up  stream,"  or  on  a  dead  level,  but  must  always  flow 
down  stream,  so  it  is  with  electricity;  the  current  is  toward 
the  low  potential,  and  with  an  equal  potential,  at  each  end  of 
a  wire  (level),  there  is  no  current  possible. 

PotcMtial  Energy— The  work  a  body  can  do  by  virtue 
of  its  position. 

Primary  Current  —  The  main  current  or  direct  current 
from  the  battery;  that  which  induces  the  secondary  current. 

Quadruples  Telegraphy— Sending  four  messages  over 
the  same  wire  at  the  same  time. 

Quantity— The  amount  of  electricity  present  in  a  body. 
All  the  most  remarkable  effects  of  the  current  of  electricity, 
such  as  electrolysis,  combustion  of  metals,  the  deflection  of 
the  galvanometer,  the  production  of  magnetism,  etc.,  are  de- 
pendent on  the  quantity  of  electricity  passing.  Its  sym- 
bol is  Q. 

Receiver — That  by  which  a  telephone  message  is  re- 
ceived, and  which  we  apply  to  the  ear. 

Recorder— The  mechanism  that  records,  or  takes  down 
the  message  spoken  into  a  phonograph,  so  named  by  Mr. 
Edison. 

Rheostat— An  instrument  used  for  the  purpose  of  varying 
at  will  the  amount  of  resistance  in  a  circuit. 

Rlieotr«p«— An  arrangement  for  reversing  the  current, 
and  often  called  the  reverser,  or  commutator. 

Regulator— The  mechanism  of  an  arc  lamp  by  means  of 
which  the  two  carbons  are  kept  at  the  proper  distance  apart. 

Relay— An  instrument  included  in  the  line  circuit  at  each 


258  ELECTRICAL  DICTIONARY 

station,  which  acts  by  the  influence  of  the  electric  currents 
on  the  main  line  to  bring  into  play  a  battery,  called  the  lo- 
cal battery,  at  the  receiving  station,  and  by  closing  the  cir- 
cuit of  such  local  battery,  to  work  a  sounder  or  register 
with  much  greater  strength  than  it  could  be  worked  by  the 
main  line  current,  which  is  weakened  by  the  distance  which 
it  has  to  travel  and  by  leakage  due  to  imperfect  insulation. 

Repeater*— A  peculiar  arrangement  of  instruments  and 
wires  whereby  the  relay,  sounder,  or  register  of  one  circuit 
is  caused  to  open  and  close  another  circuit,  thus  repeating 
or  duplicating  the  signals  sent  on  the  first  circuit. 

Reproducer— The  mechanism  that  reproduces  the  mes- 
sage spoken  into  a  phonograph.  So  named  by  Mr.  Edison, 
its  inventor. 

Kesidnal  Charge— If  a  Leyden  jar  be  fully  charged, 
allowed  to  stand  some  time,  and  then  discharged,  it  will  be 
found  to  re-charge  itself  to  a  small  extent.  This  is  called 
the  residual  charge. 

Residual  Magnetism— "When  a  current  is  conveyed 
through  the  coil  of  the  electro  magnet  the  soft  iron  core  is 
strongly  magnetized;  and  when  the  circuit  is  broken,  or 
ceases  to  flow,  demagnetization  instantly  takes  place,  but 
unless  the  iron  is  very  soft  and  pure,  a  certain  amount  of 
the  magnetism  remains  in  the  iron,  and  this  is  called  residual 
magnetism. 

Resistance —  The  obstruction  to  the  passage  of  electricity 
by  the  substance  of  the  circuit  through  which  it  passes. 
Silver  is  among  the  substances  that  offers  the  least  resistance, 
and  gutta-percha  the  most.  Silver  is,  therefore,  one  of  the 
best  conductors,  and  gutta-percha  one  of  the  best  insulators. 
Its  symbol  is  R. 

Resistance  of  Battery— The  battery  is  a  conductor  of 


AND  HIS  INVENTIONS.  259 

electricity  as  well  as  a  producer,  and  is  a  part  of  the  circuit, 
and,  therefore,  bears  its  proportion  of  the  resistance  of  the 
circuit.  It  is  also  called  "internal  resistance  of  the 
battery." 

Second— The  fundamental  unit  of  time,  and  is  equal  to 
the  time  of  one  swing  of  a  pendulum  making  86,164.09 
swings  in  a  sideral  day,  or  the  1-86,400  part  of  a  mean  solar 
day.  A  mean  solar  day  is  24  hours. 

Secondary  Batteries— Batteries,  which  are  acted  upon 
by  an  external  source  of  electricity  in  such  a  manner  that 
they  acquire  the  power  to  give  out  an  electric  current  oppo- 
site in  direction  to  that  of  the  external  source  by  which  they 
were  influenced.  The  cells  of  a  secondary  battery  contain 
plates  of  the  same  kind  of  metal,  usually  lead. 

Secondary  Currents— The  momentary  waves  of  elec- 
tricity excited  by  electro-dynamic  induction  in  a  conductor 
conveying  a  current,  or  in  a  neighboring  one.  The  wave 
which  accompanies  the  closing  of  the  circuit  is  termed  the 
initial  secondary,  and  flows  in  the  opposite  direction  to  the  in- 
ducting current;  the  other,  which  follows  the  opening  of  the 
circuit,  is  called  the  terminal  secondary,  and  flows  in  the  same 
direction  as  the  current  which  induced  it. 

Shunt— A  contrivance  for  leading  by  another  route  a  part 
of  the  current,  which,  as  a  whole,  may  be  too  powerful  for  the 
immediate  purpose.  In  this  manner  it  diverts  a  definite 
portion  of  current  aside. 

Solenoid — An  insulated  copper  wire  bent  in  the  form  of 
a  spiral,  and  having  its  ends  bent  backwards  along  the  axis 
to  the  middle  point  and  then  bent  upwards  at  right  angles 
between  two  coils  of  the  spiral.  The  typical  solenoid  of  Am- 
pere consists  of  an  arrangement  of  circular  (spiral)  currents 
of  infinitely  small  radius,  placed  side  by  side,  so  that  the 


2<5o  THOMAS  A.  EDIS01T 

planes  of  all  the  circles  are  perpendicular  to  the  line  pass- 
ing through  their  centers,  which  line  is  called  the  axis  of  the 
solenoid. 

Sounder— That  which  exactly  reproduces  the  movements 
of  a  telegraph  key  at  the  other  end  of  the  circuit,  and  by 
which  the  operator  "  takes  "  the  message. 

Specific  Gravity— The  ratio  of  the  heaviness  of  a  given 
substance  to  the  heaviness  of  pure  water,  at  a  standard  tem- 
perature, which  in  Britain  is  62°  Fahr. 

Spring  Jack— A  device  for  easily  inserting  any  loop 
into  a  line  circuit,  and  is  operated  in  conjunction  with  a 
wedge-connecter. 

Switch— An  apparatus  for  the  convenient  interchange  of 
circuits,  usually  called  a  switch-board. 

Tangent— A  straight  line  which  touches  at  any  one  point 
the  circumference  of  a  given  circle. 

Terrestrial  Magnetism— The  earth  is  a  magnet,  pos- 
sessing a  total  magnetic  power  compared  with  that  of  a  sat- 
urated steel  bar  of  one  pound  in  weight  (according  to  Goss) 
as  8,464,000,000,000,000,000,000  to  1;  which,  supposing  the 
magnetic  force  to  be  uniformly  distributed,  would  be  about 
six  of  such  bars  to  every  cubic  yard. 

Thermo-electricity— Electricity  developed  by  the  agen- 
cy of  heat. 

Transmitter— That  through  which  a  telephone  message 
is  sent,  or  into  which  we  speak  in  sending  a  message. 

Typed— Written  out  in  type  letters  by  a  type-writer. 

Type-writer— A  mechanism  for  writing  in  type  letters; 
one  who  operates  the  type-writer. 

Unit— The  base  of  any  system  of  measurement;  as  that 


EXPLANATIONS.  261 

of  length,  which  is  the  foot,  and  that  of  capacity,  the  gallon, 
etc.  And  as  electricity  has  properties,  it  therefore  has  units. 
The  unit  of  electro-motive  force  is  called  the  volt;  the  unit 
of  resistance,  ohm;  the  unit  of  current  strength,  ampere;  the 
unit  of  capacity,  farad,  and  the  unit  of  quantity,  coulomb. 

Unit  of  Force— The  force  which,  acting  upon  a  mass  of 
one  gramme  for  one  second,  moves  it  one  centimeter.  It 
was  adopted  by  the  International  Congress  of  Physicists,  at 
Paris,  in  1882,  in  connection  with  a  "system  of  units," 
known  as  the  centimeter-gramme-second,  or  C.  G.  S.  System, 
so  named  from  the  units  of  length,  mass  and  time.  This 
Congress  gave  the  name  Dyne  to  the  unit  of  force.  It  is 
also  called  "the  absolute  unit,"  and  is  the  basis  from  which 
the  electrical  system  of  measurement  is  derived.  Its  sym- 
bols are  C.  G.  S. 

Unit  of  Heat — (English).  The  amount  of  heat  required 
to  raise  one  pound  of  water  from  60°  Fahr.  to  61°. 

Unit  of  tight— (English).  The  light  of  a  spermaceti 
candle  $•  inch  in  diameter,  burning  120  grains  per  hour.  Six 
candles  weigh  one  pound;  (german)  the  light  of  a  paraffine 
candle,  20  millimeters  in  diameter,  burning  with  a  flame  5 
centimeters  high. 

Velocity —The  rate  of  motion;  electricity  travels  288,000 
miles  per  second. 

Volt— The  practical  unit  of  electro-motive  force,  or 
potential,  named  in  honor  of  the  Italian  physicist,  Volta,  the 
original  inventor  of  the  primary  battery.  It  is  equivalent  to 
100,000,000  C.  G.  S.,  or  absolute  units  of  potential.  The 
E.  M.  F.  of  one  of  Daniel's  cells  is  equal  to  1.08  Volt. 

Voltaic  or  Galvanic  Electricity— The  names  given 
to  electricity  evolved  by  chemical  action;  so  called  in  honor 
of  Volta  and  Galvani,  two  Italian  philosophers.  This  is  also 
called  Dynamical,  or  Current  electricity. 


262 


ELECTRICAL  DICTIONARY. 


Watt— The  electrical  unit  of  power,  as  proposed  by  Sir 
William  Siemens.  It  is  equivalent  to  the  volt-amperes.  One 
English  horse-power  is  equal  to  746  volt-amperes. 

Wheatstone  Bridge— An  electric  bridge  apparatus,  in- 
cluding a  rheostat  and  galvanometer  with  two  keys,  one  to 
make  and  break  the  battery  circuit,  and  the  other  to  make 
and  break  the  bridge  wire  circuit,  forming  a  system  of 
measurement  of  circuits  whereby  a  galvanometer  can  be  most 
advantageously  employed. 

Work  —  When  a  body  is  moved  against  any  force 
opposing  its  motion,  work  is  done,  and  its  amount  depends  on 
the  intensity  of  the  force,  and  the  distance  through  which 
it  is  overcome.  Thus,  if  we  lift  a  pound-weight  one  foot 
high  against  the  force  of  gravity,  we  perform  a  definite 
amount  of  work.  If  we  lift  it  twice  as  high  we  double  the 
work,  and  so  is  work  done  in  overcoming  any  force,  such  as 
the  molecular  forces  of  chemical  attraction,  magnetic  force, 
etc.,  and  the  amount  of  this  work  is  always  expressed  by  the 
product  of  the  force  by  the  distance  through  which  it  is  over- 
come. Work  is,  therefore,  the  measure  of  the  expenditure 
of  energy,  or  the  transformation  of  energy  from  one  form  to 
another,  and  has  reference  solely  to  the  amount  of  effort 
necessary  to  accomplish  a  given  result,  independent  of  time. 
Its  symbol  is  W. 


SYNOPSIS  OF  THE  PRACTICAL  ELECTRICAL  UNITS. 


UNIT    OP 

SYMBOL  OF 

NAME  OP 
UNIT. 

DERIVATION. 

VALUE  IN 
C.G.S.  UNITS. 

E.  M.  F.___ 

E. 

Volt  

Ampere  X  ohm 

10» 

Resistance  _ 
Current  ..  . 
Quantity.  . 
Capacity  .  . 
Capacity  .  . 
Power 

R. 
C. 

i 

K. 
P. 

Ohm   

Ampere  
Coulomb  ... 
Farad  
Micro-Farad 
Watt 

Volt-H  ampere 
Volt  -T-  ohm 
Amp.  per  second 
Coulomb  -5-  Volt 
1  millionth  farad 
Volt  X  ampere 

10» 

10-1 

10" 
10" 
10-  1« 
10' 

Work,  > 

TT  .  '  >  

W. 

Joule  _ 

Volt  X  coulomb 

10' 

Meat.  ) 

Amp.  X  sec  X  ohm 

107 

AND  EXPLANATIONS. 

Table  of  Weight. 


263 


GRAINS  TROT. 

POUNDS  AVOIBDUPOIS. 

0.015 

1  Centigramme  

0.154 

1  Decigramme  

1.543 

1  Gramme  

15.432 

1  Kilogramme. 

15,432.348 

2.2046 

4.4092 

6.6138 

7,000  grains  Troy  make  one  pound  Avoirdupois. 
1  Liter  is  35.275  fluid  ounces,  or  1.764  pints. 
1  Cubic  Centimeter  is  .0610  cubic  inches. 
1  Liter  is  equal  to  61.024  cubic  inches. 

Table  of  Lineal  Measure. 


INCHES. 

FEIT. 

YABDS. 

1  Millimeter 

039 

1  Centimeter 

0393 

1  Decimeter 

3937 

1  Meter  

39.370 

3.280 

1.093 

1  Kilometer.  

39,370.790 

3,280.899 

1,093.633 

Relative  Conductivities. 

Each  substance  named  conducts  better  than  the  one  that 


follows  it. 

No  conductor  is  perfect. 

Silver. 

Saline  Solutions. 

Glass. 

Copper. 

Rarefied  air. 

Sealing  wax. 

Gold. 

Melting  ice. 

Sulphur. 

Zinc. 

Distilled  water. 

.Resin. 

Platinum. 

Stone. 

Gutta-Percha. 

Iron. 

Dry  Ice. 

India-Rubber. 

Tin. 

Dry  Wood. 

Shellac. 

Lead. 

Porcelain. 

Paraffin  e. 

Mercury. 

Dry  Paper. 

Ebonite. 

Carbon. 

Wool. 

Dry  air. 

Acids. 

Silk. 

264  ELECTRICAL  DICTIONARY 

Some  Curious  Features  of  Electricity  and 
Magnetism. 

The  magnet,  in  the  exercise  of  its  attraction  upon  any 
substance,  is  equally  attracted  by  that  substance.  There  is 
no  single  or  one-sided  attraction  ;  it  is  absolutely  dualistic. 
The  magnet  seems  to  get  back  exactly  what  it  gives  and  the 
substance  gives  exactly  what  it  gets,  but  there  is  no  attrac- 
tion without  this  apparent  exchange.  All  this  is  equally  true 
with  the  electro-magnet.  Commercially,  the  magnet  oper- 
ates on  the  ad  valorem  basis;  its  consideration  in  every 
transaction  is  an  exact  equivalent,  or  there  is  no  trade;  and 
morally,  it  invariably  observes  the  golden  rule,  and  does 
precisely  as  done  by.  There  is  a  great  deal  of  philosophy  in 
a  magnet. 

When  one  kind  of  electricity  is  produced,  there  is  always 
as  much  of  the  opposite  kind  produced.  This  is  dualism 
again.  Electricity  does  not  like  to  be  "alone;"  in  fact  it 
never  is  alone,  but  invariably  has  its  companion;  it  is  two  or 
none. 

Electricity  and  magnetism,  though  in  many  respects 
similar,  in  many  are  dissimilar.  Electricity  likes  to  travel. 
Magnetism  is  decidedly  averse  to  this.  Electricity  will  go 
around  the  world  eleven  times  in  a  second  and  enjoy  it; 
magnetism  cannot  be  induced  to  leave  the  house  under  any 
consideration  whatever.  Electricity  is  a  rover,  but  mag- 
netism is  always  at  home. 

A  piece  of  green  wood  is  a  good  conductor;  let  it  be 
heated  and  dried,  it  becomes  a  non-conductor  or  insulator? 
let  it  be  baked  to  charcoal,  it  becomes  a  good  conductor 
again;  burn  it  to  ashes,  and  it  becomes  once  more  an  insu- 
lator. The  principal  element  in  wood  is  carbon. 

The  current  generated  in  a  magneto-telephone  is  estimated 
by  De  la  Rue  not  to  exceed  that  which  would  be  produced 
by  one  Daniell  cell  in  a  circuit  of  copper  wire  four  millime- 


AND  EXPLANATIONS.  265 

ters  in  diameter,  and  of  a  length  sufficient  to  go  two  hundred 
and  ninety  times  around  the  earth. 

The  tenacity  of  a  copper  wire  is  diminished  after  an  elec- 
tric current  has  for  sometime  passed  through  it.  In  an  iron 
wire  the  tenacity,  in  the  same  circumstances,  increases. 

The  conducting  power  of  carbon  is  much  lower  than  the 
metals.  Instead  of  decreasing,  as  in  the  metals,  with  a 
rise  of  temperature,  it  increases!  With  the  metals,  heat  des- 
troys the  conducting  power;  with  carbon  it  seems  to  produce 
it.  Carbon  is  a  very  singular  element  in  connection  with 
elecricity. 

According  to  Faraday,  so  small  a  quantity  of  electricity  is 
stored  in  a  Leyden  jar  that  the   decomposition  of  a  single 
grain  of  water   required   800,000    discharges   of   his   large 
Leyden  battery!     Static  electricity  is  great  in  intensity,  but' 
of  small  quantity. 

Electricity  produces  magnetism  and  magnetism  produces 
electricity. 

Wheatstone,  after  much  industry  with  very  delicate  instru- 
ments, made  up  his  mind  that  electricity  has  a  velocity  of 
288,000  miles  per  second.  Light  travels  184,000  miles  per 
second,  and  sound  1,140  feet  in  the  same  time ! 

Sulzyer,  of  Berlin,  in  1762,  is  believed  to  have  been  the 
first  who  noticed  the  peculiar  taste  occasioned  by  a  piece  of 
silver  and  a  piece  of  lead  when  placed  in  contact  with  each 
other  and  with  the  tongue.  Professor  Siemens  has  remarked 
that  we  may  yet  be  able,  in  some  way,  to  produce  food  by 
electricify.  He  intimates  that  this  is  quite  probable  in  cer- 
tain departments. 

When  called  upon  to  give  his  opinion  concerning  the  nature 
of  electricity,  Faraday  gave  utterance  to  the  following: 
"  There  was  a  time  when  I  thought  I  knew  something  about 
the  matter;  but  the  longer  I  live,  and  the  more  carefully  I 
study  the  subject,  the  more  convinced  I  am  of  my  total 
ignorance  of  the  nature  of  electricity." 


•s  THOMAS  A.  EDISON 

Recapitulation  of  Diagrams 

ILLUSTRATING 

EDISON'S  INVENTIONS. 


AND  HIS  INVENTIONS. 


Mil- 

tig.  13 ;  Micro-Tasimeter  in  section.  Fig.  14 ;  Micro-Tasimeter  in  circuit. 


THOMAS  A.  EDISON 


Fig.  9 ;  Electro-Static  Telephone. 


AND  HIS  INVENTIONS. 


The  Phonograph  in  operation. 


11 


Phonographic  Records  under  the  Microscope. 


AND  HIS  INVENTIONS. 


THOMAS  A.  EDISON 


Edison's  Electric  Pen. 


Fig.  i.  Fig.  i. 

Fig.  i.   Carbon  Telephone— Interior.  A  A,  Iron  Diaphragm;  B.India  Bubber;  C,  Ivory;  D, 

Platraa  Plate ;  E,  Carbon  Disk ;  G,  Platina  Screw.    Fig.  2.    Exterior 

View  of  Edison's  Telephone. 


AND  HIS 


The  Phonometer 


THOMAS  A.  EDISON 


AND  HIS  INVENTIONS. 


Edison's  Electric  Light. 


AND  HIS  ItfVEN'TIONS. 


AND  SIS  INVENTIONS. 


Th»  Edison  Municipal  In 


Ediroa's  Pyro-Magnetio  Dynamo. 


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UC  SOUTHERN  REGIONAL  LIBRARY  FACILITY 


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